@arubislander Yes, I never unlocked it and always used the Update function. From the messages I read I was convinced I can only proceed if I agree to unlock (and lose all data).
Now it's too late to test if it would have been possible to not lose the data...

@arubislander Thanks for that hint. I did it with a VM this time because I needed it anyway.

Unfortunately, I lost all data on the phone.

It was a Volla with pre-installed UT and the ubports-installer needed to unlock the device. I was warned that I will loose all data but I had no choice -- the phone was dead, anyway...

It looks to me as if the fresh installed OS is a bit different (in a positive sense) than what I had before but for now it's just a feeling.

@MrT10001 It seems that is what I need to do.

I tried to do it with a Raspberry Pi with snap but ubports-installer isn't available for armhf:

$ sudo snap install ubports-installer
error: snap "ubports-installer" is not available on stable for this architecture (armhf) but exists on other architectures (amd64, arm64).

...

@MrT10001 I hoped there is another way. I'm on Gentoo which to my knowledge has no package for the installer. I tried the AppImage but that needs an older libfuse than I have installed. Do you perhaps know if I can use a Raspberry Pi to use the UT installer out of the box?

@Ian Yes, thanks for the link.

Hi,

today, I was noticed about an update being available and as so often in the past I just installed it.

This time, the phone doesn't start after the update.

By pressing some keys after starting the phone I get a
"..ports Recovery" menu but that doesn't help.

I searched the web for more information, without success.

What options do I have, to get my phone back working?