Microphone not working on iPhone 7

This happened just a few hours ago, but the microphone on my iPhone has stopped working. Whenever I take a video, there is no audio and the mute volume button (beside the play button) is greyed out and I can't press it. When I call someone they can't hear me, and the speaker button is greyed out. When I put headphones in, nothing happens and any music or anything I play just comes out of the speaker. I also can't record voice memos or send voice messages, whenever I press the record button nothing happens. My problem is similar to this one: iPhone 7 + no microphone during calls or … - Apple Community, besides the software part. I talked to Apple support and we tried different methods (including updating my phone), which didn't work. They suggested I bring the phone in so they can look at it. I just wanted to see if anyone had the same problem, and how they fixed it before I take it to the Apple Store.