Error when adding new cards

Error
An error occurred. Please use Tools > Check Database to see if that fixes the problem.
If problems persist, please report the problem on our support site. Please copy and paste the information below into your report.
Anki 2.1.35 (84dcaa86) Python 3.8.0 Qt 5.14.2 PyQt 5.14.2
Platform: Windows 10
Flags: frz=True ao=False sv=1
Add-ons, last update check: 2020-11-13 14:00:53

Caught exception:
Traceback (most recent call last):
File “aqt\webview.py”, line 493, in handler
File “aqt\editor.py”, line 483, in
File “aqt\addcards.py”, line 191, in _addCards
File “aqt\addcards.py”, line 178, in addNote
File “anki\collection.py”, line 345, in add_note
File “anki\rsbackend_gen.py”, line 339, in add_note
File “anki\rsbackend.py”, line 267, in _run_command
anki.rsbackend.DBError: DBError { info: “SqliteFailure(Error { code: CannotOpen, extended_code: 14 }, Some(“unable to open database file”))”, kind: Other }

Anytime i try to add a new card i get this error. I have tried everything, restarting holding shift, etc. I even opened up backups but I just cannot add a new card. Plz and help.

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