Microphone on Dynamic Island
For iPhone 14 pro, mic icon remains active on dynamic island. Every time restart is required to make it disappear. After restarting after few number of phone call, it again remains active on dynamic island.
iPhone 14 Pro
Question marked as
Read this page from the iPhone User Guide. Among other things, it suggests how to learn what app is accessing the microphone (visible in Control Center).
Control access to hardware features on iPhone - Apple Support