Why don't you go? SMS Xiaomi Redmi phone: full analysis of causes and solutions

You are trying to send important messages. SMS From your Xiaomi Redmi, but the message persists - no errors, no notifications, just silence? Or does the word "Not sent" appear and repeated attempts do not help? This problem is familiar to many owners of Redmi smartphones (from budget Redmi). 9A The Redmi Note 13 Pro is the flagship+), and its causes can be hidden both in the settings of the phone and in the work of the mobile operator.

Unlike messengers like WhatsApp or Telegram, SMS depends on the stability of communication with the cell tower and correct operation SIM-And 60 percent of the time, it's not hardware failures, it's software constraints. MIUI configuration errors APN — They can be fixed by themselves in 5-10 minutes, and in this article we will look at all possible causes, from the banal (mobile internet disabled) to the exotic (dual-SIM conflict), and give clear instructions for each of them.

If you're in a hurry, use the quick checklist at the end of the article. For in-depth analysis, read on: we've tested each method on Redmi Note 12 Pro, Redmi. 10C and POCO X5 firmware MIUI 14 and HyperOS.

1.Problems with SIM-Card: From physical damage to lockdown

The first thing you need to check is yourself. SIM-Even if it looks intact, microcracks on the chip or contamination of contacts can interrupt communication with the network. On Xiaomi Redmi with hybrid slots (for example, Redmi Note 11 Pro), it is common for a user to insert a second SIM or memory card, but not dense - this leads to loss of signal.

How to diagnose:

• 🔍 Visual inspection: get out SIM-check for scratches, chips or oxidation of contacts (gold stripes) wipe them with a wipe or an alcohol wipe.
• 📶 Test on another phone: insert SIM to another machine. SMS There is no problem with the operator (see section 2).
• 🔄 Slot reboot: Turn off the phone, pull out and insert again SIM, Turn on the device. SIM Try to swap slots in places.

Pay special attention to nano.-SIM (The format used in Redmi 12 If you cut the regular one. SIM If you're nano-sized, you're at risk of chip damage, so you can order a duplicate card from the operator, it's free.

⚠️ Warning: If the phone is making an error SIM-Card not supported or Ineligible card, this could mean hardware lock IMEI (For example, after firmware is unofficial, in which case restoration is required. IMEI.

2. Restrictions by the mobile operator

Communications operators (MTS, Beeline, Tele2, MegaFon) can block the sending SMS for several reasons:

• 💰 Unpaid bill: When a negative balance is reached, some operators first turn off SMS, And then the calls.
• 🚫 Suspicious activity: Mass messaging (even random) can lead to temporary blocking.
• 📡 Technical work: check the status of services on the operator’s website (for example, the MTS fault map).
• 🔒 Tariff restriction: on some tariffs (for example, "For laptop" from Tele2) SMS paid-off.

How to check:

1. Call the operator’s short number (e.g. *111# for MTS) and request the status of the services.
2. Try sending it. SMS If you leave, you have to go to another operator's number (for example, from MTS to Beeline.
3. Check the fare: some “Internet tariffs” (for example, “All for 300” from Tele2) do not include SMS packet.

If the blockage is confirmed, the decisions:

• 💳 Refill the balance (even 10 rubles) and reboot the phone.
• 📞 Call the operator's support and clarify the reason for the lock.Redmi with HyperOS may require manual settings input APN (see section 4).

3.Firmware failures MIUI or hyperos

Xiaomi Operating System — MIUI (or the new HyperOS) — known for its features, which sometimes break basic functionality. MIUI 14 was a bug that prevented the Message application from connecting to the network to send SMS, if the phone is activated VPN power-saving.

Typical symptoms of a software failure:

• ❌ Messages don't leave, but incoming SMS come.
• 🔄 The sending button “hangs” or spins indefinitely.
• 📱 After the reboot, the problem disappears, but then returns.

Solutions (from simple to complex):

1. Cleaning the Messages app cache: Go to Settings → Annexes → Application management. Find Messages, press Storage. → Clear the cache.
2. Resetting network settings: Settings → SIM-maps and mobile networks → Resetting network settings ⚠️ Warning: This will delete saved Wi-Fi passwords and Bluetooth settings.
3. Firmware Update: Check the relevance of the software in Settings → The phone. → System Update. If you have an update, install it. For Redmi with HyperOS, it is recommended to use a stable version (not beta!).

Check the balance. SIM-map|Turn it off. VPN/proxy|Delete the cache of the application "Messages"|Reboot the phone.|Update the firmware (if there is an update)-->

If the problem persists, try an alternative. SMS-Application (e.g. Textra or Pulse) SMS). If they send messages, the fault of the standard application MIUI.

4. Incorrect settings APN (point)

APN (Access Point Name is the “address” by which the phone connects to the operator’s network to transfer data and SMS. If the settings are lost (for example, after the update) MIUI shift SIM), Messages may not be sent even if the internet is working.

How to check and fix APN Xiaomi Redmi:

1. Go to: Settings → SIM-maps and mobile networks → [choose SIM] → Access points (APN)
2. If the list is empty or there are several profiles, click Add and enter your operator’s details (see the table below).
3. Save the settings and restart the phone.

If, after the change, APN SMS still:

• 🔄 Delete all the saved ones. APN Add only one profile (for your operator).
• 📱 Check that the correct profile is selected (check next to the name).
• 🔧 If you have Redmi with dual-SIM, reset the settings for both cards.

💡

On some tariffs (for example, "For tablet" from MegaFon) APN for SMS Check with the operator by phone *505# or in the chat support.

5.Dual-SIM conflicts

Xiaomi Redmi smartphones with support for two SIM-Cards (e.g. Redmi Note 11 Pro)+ Redmi 10 2022, sometimes facing conflict when sending SMS. It's because of this:

• 📶 Network Priority: If one SIM used 4G, And the second one is for calls, SMS They may be stuck in line.
• 🔄 Automatic Switching: Smart Dual Function SIM into MIUI It can redirect messages to inactive SIM.
• 🚫 Operator locks: some tariffs do not support the operation of two SIM simultaneously.

How to configure Dual-SIM for proper sending SMS:

1. Open: Settings → SIM-maps and mobile networks → Dual-SIM settings
2. Set a priority for SMS: Choose. SIM, which you want to send messages by default. Turn off the Request every time option (if it interferes with the request).

Automatic data switching

If the problem remains:

• 🔄 Reboot the phone with both of them. SIM.
• 📱 Change it. SIM occasionally (first) ↔ second-second).
• 🔧 In the extreme, turn off the second. SIM and check the shipment. SMS single-card.

6. Damage. IMEI or

If you have ever stitched your Xiaomi Redmi custom firmware (for example, LineageOS or Pixel Experience), or after resetting to factory settings, you stopped going SMS — There's a good chance he's gone. IMEI. This unique identifier connects the phone to the operator’s network, and without it, the device cannot send messages.

Signs of a problem with IMEI:

• 📵 There is no network icon in the status bar (or it is grey).
• 🔢 B Settings → The phone. → General information instead of IMEI displayed zeros or unknown.
• 🚫 The operator is not automatically determined.

How to repair IMEI Xiaomi Redmi:

⚠️ Attention: incorrect change IMEI This method is illegal and may result in the device being blocked. IMEI He was not changed after the supplication, but he was not changed.

1. Find out the original IMEI: Look at the phone box or under the battery (if removable) or type in the phone number *#06# (if you have a removable one). IMEI It is displayed there, but not in the settings - the problem is the firmware).

Engineer Mode

Qualcomm

1. Enter in the dialer: ##4636##


2. Go to Phone Information.




3. Scroll down to MTK (or DSDS Information for Dual-SIM).




4. Enter the IMEI for each slot and click Update.

MediaTek

Maui META

If IMEI If you can't recover it, you can contact Xiaomi with a check to buy it.

7.The Impact of Third-Party Applications (VPN, Antiviruses, optimizers)

Many Xiaomi Redmi users install apps to save traffic, block ads or speed up the internet.Some of them may interfere with sending SMS, intercepting network requests or blocking system services:

• 🔒 VPN and proxy: Turbo VPN, Psiphon, AdGuard (mode) VPN).
• 🛡️ Antivirus: 360 Security, Clean Master, Avast.
• ⚡ Optimizers: DU Speed Booster, Game Turbo (built-in) MIUI).
• 📵 Adblockers: Blokada, NetGuard (if you are too aggressive).

How to check the impact of third-party applications:

1. Launch your phone in Safe Mode: Press the Power button → Hold it down. → Press Safe Mode. This mode only runs system applications. Try sending it. SMS.

1. Get back to normal.
2. Turn it off. VPN/proxy in settings.
3. Remove suspicious applications by checking for shipment SMS after each removal.

And you can focus on AdGuard and blockers like that. They can filter. SMS-traffic if you have operator domains on the blacklist. Open AdGuard settings → Filters → Disable all user rules.

Hardware malfunctions: from antenna to communication module

If all the software methods have been tried, but SMS They still don't ship -- the problem could be hardware:

• 📡 Antenna module damage: often occurs after a phone falls or moisture is ingested (even if everything is intact on the outside).
• 🔌 Oxidation of contacts SIM-cards: over time, slot contacts can become covered with a raid, which worsens the connection.
• 🔋 Communication module malfunction: on Redmi with MediaTek processors (e.g. Redmi) 9C) This is more common than on Snapdragon.
• 🔄 Failure after repair: if the phone was disassembled (for example, to replace the screen), the antenna plume could be damaged.

How to diagnose a hardware malfunction:

1. Check the signal level: Enter the dialer ##4636##. Go to Phone Information → See the value of dBm (norm: from -70 before -110; less -120 — slug).
2. Test your phone in different places: SMS Do not leave even in open areas (where the signal is usually stable.
3. Look at the indicators: If the network icon flashes or disappears, the antenna may malfunction. If the phone overheats when you try to send it. SMS — failure.

Decisions:

• 🔧 Clearing contacts SIM-cards: use eraser or alcohol. Do not use abrasive materials!
• 🛠️ Diagnostics at the service center: if you suspect an antenna or communication module, contact the specialists.
• 📱 Replacement SIM-Cards: sometimes the problem is solved by a new card (especially if the old one lasts more than 5 years).

💡

If the phone falls or gets wet, don’t try to disassemble it yourself – the risk of damaging the antenna module is too high. In Xiaomi service centers, diagnostics take 10-15 minutes and are often free.

🚀 Quick checklist: what to do right now

If you don’t have time to read the entire article, follow this algorithm (from simple to complex):

Check the balance. SIM-cards (dial *100# or similar)|Reboot the phone.|Clear the cache of the "Messages" application (Settings) → Annexes → Communications → Warehouse)|Check the settings. APN (You should only have one profile for your operator)|Turn it off. VPN/proxy and antivirus|Try sending it. SMS via another application (e.g. Textra)|Put it in. SIM to another phone and check the shipment|Reset network settings (Settings) → SIM-map → Resetting network settings)|Update your firmware to the latest stable version-->

If none of the points helped – the problem is more hardware or connected with the lock. IMEI. In this case:

1. Check it out. IMEI (Type *#06#. If you replace the zeros, restore it (see section 6).
2. Contact the Xiaomi service center or the operator (if you suspect a blockage).

❓ Frequently asked questions