Open the Settings app
Tap Privacy & Security
Tap Microphone
Turn on the switch for the app you want to use
Open the app and allow microphone access if prompted
Check that Silent Mode is not affecting your audio input
Make sure the app is not blocked by Screen Time restrictions
Restart the iPhone if the microphone still does not work
Test the microphone in Voice Memos or Camera video recording
Clean the microphone openings if needed
Update iOS if the issue continues