Hi, I just wanted to let you know that I was able to solve the problem.
I followed the instructions found in the fairphone forum of others who had the same problem.
I disassembled the fairphone and unscrewed the camera module.
I cleaned the contacts with a cotton bud soaked in alcohol.
Reassembled everything, the camera app works great since yesterday.
I hope it keeps working.:cat_face_with_wry_smile: