When I click the button to study the first card show, and when I click to show the answer a message appears. The message that appears is the showed below:
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 2.1.49 (dc80804a) Python 3.8.6 Qt 5.14.2 PyQt 5.14.2
Platform: Windows 7
Flags: frz=True ao=False sv=2
Add-ons, last update check: 2023-02-16 11:16:55
Caught exception:
Traceback (most recent call last):
File “aqt\webview.py”, line 541, in handler
File “aqt\reviewer.py”, line 704, in _onTypedAnswer
File “aqt\reviewer.py”, line 383, in _showAnswer
File “aqt\reviewer.py”, line 759, in _showEaseButtons
File “aqt\reviewer.py”, line 846, in _answerButtons
File “aqt\reviewer.py”, line 832, in but
File “aqt\reviewer.py”, line 856, in _buttonTime
File “anki\scheduler\v2.py”, line 1140, in nextIvlStr
File “anki\scheduler\v2.py”, line 1035, in nextIvl
File “anki\scheduler\v2.py”, line 910, in _nextRevIvl
TypeError: ‘>’ not supported between instances of ‘NoneType’ and ‘int’