1. You can go to the settings-sound-in the mobile phone to see if the mute-vibration switch is turned on.

2. press the volume plus key to turn the sound to the maximum.

3. Try upgrading the mobile phone to the latest version. You can go to Settings-General/More Settings-System Upgrade-Check the update immediately, download the upgrade package according to the prompt, click Check and Install, and the mobile phone will restart and automatically enter the upgrade mode.

4. You can try to restore all the settings, and go to Settings in the phone-More Settings-Restore Factory Settings-Restore Factory Settings (this operation will not clear the data in the phone).

5. If the above methods still cannot be solved, it is recommended that you take your mobile phone, warranty card and purchase certificate to the nearest after-sales service center for testing and processing. The contact information and address of the after-sales service center can be found in the Settings-More Settings-After-sales Service menu.