VS code not underlining errors

Question

Problem: VS Code is not underlining errors (with wavy red underlining) as it used to.

Problem exists for me and my friend (macOS and Windows)

Linter: mypy

settings.json:

{
"python.pythonPath": "/Users/username/.pyenv/versions/3.8.5/bin/python",
"python.linting.pylintEnabled": false,
"python.linting.mypyEnabled": true,
"python.linting.enabled": true
}

After running the script VS will underline found errors, but still wont underline any newly written errors.

When typing anything in the script, OUTPUT:python shows the following (or simular), which i dont understand and am not sure if its relevant:

Error 2020-11-09 20:20:07: stderr jediProxy Error (stderr) /Users/username/.vscode/extensions/ms-python.python-2020.10.332292344/pythonFiles/completion.py:584: DeprecationWarning: Deprecated since version 0.16.0. Use Script(...).get_names instead.
  jedi.api.names(

Error 2020-11-09 20:20:27: stderr jediProxy Error (stderr) /Users/username/.vscode/extensions/ms-python.python-2020.10.332292344/pythonFiles/completion.py:592: DeprecationWarning: Providing the line is now done in the functions themselves like `Script(...).complete(line, column)`
  script = jedi.Script(
/Users/username/.vscode/extensions/ms-python.python-2020.10.332292344/pythonFiles/completion.py:592: DeprecationWarning: Deprecated since version 0.17.0. Use the project API instead, which means Script(project=Project(dir, sys_path=sys_path)) instead.
  script = jedi.Script(

Error 2020-11-09 20:20:27: stderr jediProxy Error (stderr) /Users/username/.vscode/extensions/ms-python.python-2020.10.332292344/pythonFiles/completion.py:105: DeprecationWarning: Deprecated since version 0.16.0. Use Script(...).get_signatures instead.
  call_signatures = script.call_signatures()
/Users/username/.vscode/extensions/ms-python.python-2020.10.332292344/pythonFiles/completion.py:230: DeprecationWarning: Deprecated since version 0.16.0. Use Script(...).complete instead.
  completions = script.completions()

Thanks for helping!