Something similar happened to me.
You might be able to fix it by cleaning the contacts. Take a look to this post:
As for the image disappearing completely, here’s how I fixed it (open the link for the full text and images):
Hello againFirst of all, thank you very much to everyone for your suggestions and advice. It is often said, but it is true that the best thing about Fairphone is this community. This morning I went to buy a brush with metal bristles to clean the contacts (the ones in blue in this picture), and I proceeded to clean the contacts of the screen of my FP3 as follows: Dip a cotton swab in isopropyl alcohol and wet the contact area to be cleaned. Gently scrape the contact with the metal bri…
Best wishes and good luck
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