coaching-2021 Very interesting!
Should this happen in the future, I would suggest shaking the device and checking out the Logbook as you try to authenticate for your user. You can switch the sensitivity over to TRC to get more information on the internals. It may be a lot to dig through, the higher up you go in sensitivity, but this might shed some light on what exactly is going wrong.
Note that at the INF level, there should be no sensitive information in the logs and you should be able to share it with me safely in a private message; though below that level there might be private information you don't want to divulge, so you may want to either parse this yourself or maybe try and reproduce the issue with a test user instead.
I'll keep your report in mind. Glad Spectre was able to successfully recover your information, though.