Deactivating O2 and activating Fraenk did not help.
Still the boot loop.
The green Fairphone Logo appears, transforms into a single line and the phone reboots several times. After several failed attempts, it falls back to Android 13.
Now I will try with both SIM cards disabled
I really need the update since my health insurance app stopped being supported on Android 13. And I would prefer having recent security updates.