1. Due to the usage problem, when you hold the phone with your right hand, your right thumb may block the microphone feeding hole (the hole on the left side of the USB charging connector) at the lower side of the phone, causing no sound from the microphone when you make a sound to the phone; simply move your right thumb to return to normal mode.                          

2. Check if there is any foreign matter blocking the main microphone, if so, it is recommended to use alcohol to clean it up.

3. Check if a third-party call app or recording software is installed. If so, please uninstall the third-party software.

4. Try to call others after ensuring that the phone signal is normal. If the signal is normal, the receiver of the other party’s phone is faulty.

6. Open the recording system software to check if there is any problem. If it is unable to record, please contact our corresponding platform for after-sales service.