PRS-T1 Memory formatting

Yesterday, my PRS-T1 had some kind of catastrophic crash. I reset it to factor defaults but can't put any books on it.

Calibre gives me the following error:
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calibre, version 3.48.0
ERROR: Error: Error communicating with device

unable to open database file

Traceback (most recent call last):
File "site-packages/calibre/gui2/device.py", line 90, in run
File "site-packages/calibre/gui2/device.py", line 513, in _books
File "site-packages/calibre/devices/prst1/driver.py", line 166, in books
File "site-packages/calibre/devices/usbms/driver.py", line 304, in books
File "site-packages/calibre/devices/prst1/driver.py", line 249, in sync_booklists
File "site-packages/calibre/devices/prst1/driver.py", line 278, in update_device_database
OperationalError: unable to open database file

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I tried formatting the internal memory but it never finishes after hours of waiting.

Any ideas about what else I can try?