Thanks for the clarification.
It seems that closing the biometric auth dialogue silently failes sometimes on your device. Unfortunately, we can’t do more than asking the OS to close it. The only thing we could do is to optionally disable the prepare unlock via the settings so that when it is deactivated, it first authenticates via biometrics and when finished we communicate with onedrive. But that’s not really nice either because the unlock will take longer and we have to implement this extra, but the way it is right now it seems to be really broken on your device.