Did you try to reach their customer support?
Yep. I phoned them and they first repeated what was already written and then declared the error to be on my side, I should "delete some files".
That's because I ask here.
I think that at least unlock the process in order to retry should be easily possible.
You can retry again and again, it does not help.
There seems to be a bug in the software that seeks to take the picture on the phone and send it to their security service (onifodo?), maybe depending on Android / camera / Browser version.
Accepting the passport picture only via smartphone (and not website, upload, email) seems to be some security idea, stupid enough.
since Bitcoin is on a rise, for now you lose nothing if you wait
No, my account balance is in Euro, not BTC.