Lines on front camera

(1) Try and Force Restart your iPhone EXACTLY as shown below and see whether that resolves the issue:

• Press and quickly release Volume UP button
• Press and quickly release Volume DOWN button
• Press and Hold the SIDE button until an Apple logo appears and then release the Side button (Can take up to 20 seconds. (DO NOT release Side Button when invited to Slide Power OFF). 

(2)  If that does not help, then contact 👉 Official Apple Support OR you can always get your iPhone examined at the Apple Store 👉 Genius Bar Reservation and Apple Support Options or at an Authorized Service Center for further diagnosis and a resolution.

Axel F.

Hello _reisle!

For this issue, you may have to Contact Apple Support directly, or get your camera looked at a Genius Bar.

However, you can try the tips here: If the camera or flash on your iPhone, iPad, or iPod touch isn't working - Apple Support

I hope this is helpful. Good Luck!