Causes:
1. The phone volume is muted.
2. The speaker holes are clogged by dust or other objects.
3. The phone is accidentally connected to a Bluetooth device, and the sound is coming from the Bluetooth device.
4. There is an issue with the playback source.
Solutions:
1. Press the volume + button to try again.
2. Remove the phone case and clean the speaker holes to try again.
3. Turn off the Bluetooth to try again.
4. Restart the phone and change to another playback source to try again.
If the above methods do not solve your problem, please back up your data in advance and contact the realme Service Center with your purchase certificate for further assistance.