Work through these checks in order
Confirm sound is not routed to Bluetooth, headphones or another output.
Record a short voice memo or video to see whether the microphone captures sound.
Visible debris can block speakers or microphones, but avoid liquid and sharp tools.
A case or screen protector can cover an opening or interfere with a microphone.
If one calling app fails while system recording works, focus on that app’s permissions and settings.
Before an erase, restore or repair decision
Confirm what data is backed up, what a reset or restore will remove, and whether you still need access to account credentials or authentication methods stored on the device.
When professional service makes sense
Hardware damage, repeated power failure, liquid exposure, battery swelling, damaged ports, broken displays and problems that persist after low-risk software checks can require qualified inspection.