B2 stuck in "Checking storage..."

My Bangle.js2 is stuck again. This time it is stuck in "Checking storage...".

It happened during app update via the Android Bangle.js GadgetBridge app: suddenly the app loader showed 0 installed apps (previously it was ~30 apps installed).

Then i tried to launch the launcher but the watch said "no launcher found." I tried to reboot the watch and now it hangs in "Checking storage...".
I already flashed a new edge build firmware (i was on 2v15.~100 before) via DFU but after flashing was successful it is stuck again.

I hope anyone can help me :)

Please can you try what's mentioned in this thread? https://forum.espruino.com/conversations­/380541/

Ideally you could read out the contents of flash like @SloFlo did (feel free to send them to me privately if you're worried about personal info) and I can the reproduce here and try and fix the root of the problem

After a few tries i was able to flash a firmware via the apploader (not via DFU) and the watch finally booted again.

Thanks to @halemmerich for the tipp.

No idea yet how to reproduce this.

... but flashing a cutting edge firmware fixed it?

Only via Firmware app from the app loader - not flashing via DFU.

Ahh, ok - so it wasn't actually stuck at Checking Storage - it was all still connectable by Bluetooth? It's just that somehow all the files had got lost and no clock/launcher/etc got loaded?

When you flashed a new firmware, did all your files come back?

Yes it looked like the storage was actually empty.

All files were lost after flashing the firmware.