Step 1: If the SIM card is not properly inserted, the SIM card cannot be found.
The solution is to shut down the phone first, deduct the rear cover of the phone, and re-plug the sim card. Pay attention to the sim direction,
Step 2: System configuration problems
If the SIM card is re-inserted as shown in the preceding method, we can choose SIM card management on the mobile phone system to check whether sim1 or sim2 is enabled, as shown in the following figure.
Step 3: system problems
If it still cannot be a problem with the mobile phone after adjustment, we can restore the factory settings of the mobile phone and remind you to back up your personal data, such as the address book, text message, and photo. The resetting method is as follows: go to system settings-backup and reset
Step 4: hardware problems
If the above three steps cannot solve your problem, you just need to check whether it is a hardware problem or the SIM card has been useless for a long time. Let's try to clean it up on the mobile phone.