Definition for rule 'simple-import-sort/sort' was not found simple-import-sort/sort

It may be that you're using v6.

It looks like v6 doesn't have a simple-import-sort/sort rule, see usage in the README. This was a change from v5 on Nov 15.

You probably need to make the following change:

- 'simple-import-sort/sort': 'error',
+ 'simple-import-sort/imports': 'error',