on 08-02-2021 19:08
on 08-02-2021 19:11
on 08-02-2021 19:12
on 08-02-2021 19:12
Do you have a cover on the phone
Try cleaning the speaker port gently with a pin
Reboot the phone
on 08-02-2021 19:13
on 08-02-2021 19:13
Unless you have something covering the earpiece, it would suggest it is faulty (is volume turned up full when on the call?).
Contact the phone manufacturer for a diagnostic check.