Hello from Germany. I’ve finally managed to do it after 20 reboots. My problem was that I waited too long. I only restarted as soon as the “I” was displayed.
Try this: Hold down the on/off switch until the screen goes black. As soon as the word “Fairphone” appears in green and the Android logo below it, hold down the on/off switch until the screen goes black again. You do this about 7-8 times. At some point I was suddenly back in.
Good luck!
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