If you cannot hear anyone but they can hear you, which may likely be due to some internal speaker issues with your phone. Check these easy steps first:
- Restart your phone, disconnect all possible external sound devices from your phone, such as wired headphones and Bluetooth devices.
- Make a call, or listen to voicemail on your phone, use the volume keys to turn the sound up (depending on your phone model, you can see the volume bar on the screen when you press the volume keys).
- Use your phone in-call options, switch to the speaker mode to check if that resolves the problem (for more info, see the user guide of your phone).
- If you can hear the other person in the speaker mode, check that no any objects are blocking the internal speaker opening on your phone, such as an accessory case or a protective film.
- If you still do not hear sound from the internal speaker, connect a compatible wired headphone. Push and pull the audio plug gently with your finger, and disconnect it. If this helps, check the audio jack connector for any dust or dirt.