Im new to this community so i dont really know what to say. There is an error when importing a file

Import fehlgeschlagen. Die Fehlermeldung lautet:
Traceback (most recent call last):
File "aqt\importing.py", line 404, in on_done
File "concurrent\futures_base.py", line 432, in result
File "concurrent\futures_base.py", line 388, in __get_result
File "concurrent\futures\thread.py", line 57, in run
File "C:\Users*NAME*\AppData\Roaming\Anki2\addons21\175027074\anki\importing\anki1.py", line 17, in run
res = u.check(self.file)
File "C:\Users*NAME*\AppData\Roaming\Anki2\addons21\175027074\anki\upgrade.py", line 39, in check
res = self._fix(self.tmppath)
File "C:\Users*NAME*\AppData\Roaming\Anki2\addons21\175027074\anki\upgrade.py", line 108, in _fix
from oldanki import DeckStorage
ModuleNotFoundError: No module named 'oldanki'

Any way to fix this or is the file forever broken?
Best regards

I'm returning to Anki after some time. I have an old deck that I'm wanting to pull in, but had this plugin recommended based o the number. Now with the plugin installed, I get this new error message. The version used to develop the old deck was 2.0.3.

==== Stack Trace provided by the app: ========================
Error
An error occurred. Please start Anki while holding down the shift key, which will temporarily disable the add-ons you have installed.
If the issue only occurs when add-ons are enabled, please use the Tools > Add-ons menu item to disable some add-ons and restart Anki, repeating until you discover the add-on that is causing the problem.
When you've discovered the add-on that is causing the problem, please report the issue to the add-on author.
Debug info:
Anki 2.1.54 (b6a7760c) Python 3.9.7 Qt 6.3.1 PyQt 6.3.1
Platform: Windows 10
Flags: frz=True ao=True sv=2
Add-ons, last update check: 2022-07-13 22:05:17

Traceback (most recent call last):
File "C:\Users\Administrator\AppData\Roaming\Anki2\addons21\175027074\anki\importing\anki1.py", line 29, in run
deck = u.upgrade()
File "C:\Users\Administrator\AppData\Roaming\Anki2\addons21\175027074\anki\upgrade.py", line 133, in upgrade
self._upgradeSchema()
File "C:\Users\Administrator\AppData\Roaming\Anki2\addons21\175027074\anki\upgrade.py", line 199, in _upgradeSchema
from anki.utils import minimizeHTML
ImportError: cannot import name 'minimizeHTML' from 'anki.utils' (unknown location)

Errors out, unfortunately. Manually entering the .anki filename (since it's not shown when .anki is selected for "Files of type:", only when that is set to something else) and opening it only yields:

Traceback (most recent call last):
  File "~/.local/share/Anki2/addons21/175027074/anki/importing/anki1.py", line 27, in run
    deck = u.upgrade()
  File "~/.local/share/Anki2/addons21/175027074/anki/upgrade.py", line 128, in upgrade
    self._upgradeSchema()
  File "~/.local/share/Anki2/addons21/175027074/anki/upgrade.py", line 214, in _upgradeSchema
    _addSchema(db, False)
  File "~/.local/share/Anki2/addons21/175027074/anki/storage.py", line 81, in _addSchema
    """ % ({'v':SCHEMA_VERSION, 's':intTime(1000)}))
NameError: name 'SCHEMA_VERSION' is not defined

Using Anki 2.1.36 1e37e6ca and a new profile.