Hello there sir my name is jacob I will assisting you with your issues your having today so first things first let’s do a normal mic check as you have stated above your mic dose not work in memos app and also calling users on the Apple device
so first things first I will need you to do me a favour head to the camera app if your on iPhone 10 X iPhone XS iPhone 11 iPhone 12 and iPhone SE remastered
please try recoding yourself in the camera app the reason I’m asking you to do this is because on those Apple devices there is more then just one mic there is a about 4 and one front facing mic that is only used for videos and calls on some platforms and applications
so by using the camera app if it dose work then that means we have tracked the source of the issue to just one select microphone and it can be fixed by taking your phone to the Apple support store or taking it to your local retail or Phone provider if you have one such as bell verzion virgin mobile and T mobile
however that said if the mic is not working In the video by Camera app then you will have to also understand that your iPhone might have encountered a glitch preventing your Apple device from allowing audio inputs from coming into your Apple device and also maybe dirt inside it