Causes:
1. Your phone has no credit left.
2. Your SIM card is not working properly.
3. The signal is too weak for your phone to send or receive SMS.
4. The SMS is marked as spam or blocked by your settings.
5. The specific contact or the third-party app has some issues.
Solutions:
1. Please get in touch with your operator to recharge your phone.
2. If you see an icon in the status bar that shows
or
, it means your SIM card is not recognized. You may need to go to your operator and get a standard SIM card replacement.
3. Please try moving to a place with a better signal and try again.
4. Please check your spam and blocked numbers settings. If you want to unblock some numbers, you can disable this feature by following these steps:
Spam: SMS > Three lines on the top left > Settings > Spam & blocked conversations.
Blocked numbers: SMS > Three lines on the top left > Settings > Spam & blocked conversations > Three dots on the top right > Disable Unknown/Blocked numbers.
5. If you cannot receive SMS from a specific number or verification code from a third-party app, you may need to contact the operator of that number or the app developer.
6. Please try to update the system version to try.
If none of these steps solve your problem, please back up your data and visit the nearest authorized realme service center for further assistance.
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