About Errors On iPhone 7 Plus

Hello, I am a user from Vietnam. I have a 7 plus phone that is currently experiencing the following error. Loss of Vibration throughout the device (both vibration when pressing the home button and warnings), weak wifi / mobile signal, loss of proximity sensor, and especially when recording video, both the front and rear cameras have no sound (only sound noise shhh shhh, And when i start pressing the video recording button, the recording process will not happen immediately but will delay about 3-5 seconds ). But what's more remarkable is that when I record, make calls, or even make video calls, the microphone still works normally!. I took the device to repair places in my country, but most of them returned the device. Although I am not a professional repairman, I also want to know the reason for those errors on the phone. my phone 7 plus. Can someone with experience explain it to me?? Thank you very much for listening to the question!