Question: iphone 7 front camera showing green line
So my iphone 7 and I've had it for a year now ,today I was on skype with a friend when suddenly this green line showed up and it won't disappear. It is seen only when I use my front camera for the camera app or any other app that requires the front camera. I've turned my phone on and off multiple times and also tried leaving it off for an hour but still it has not disappeared. I thought it was because I didn't update my phone so I updated it to the latest IOS but there was still no change. Any idea what this could be? its really annoying, please help!
iPhone 7, iOS 11.1