Is the test failing because the test is wrong, or the test logic the test is checking is wrong?

@code-review-doctor thanks for fixing the typo in the test!

I haven't checked but I think you need to change
case = make_recipe("legalaid.case")
into something like
case = make_recipe("legalaid.case", personal_details=None)

As the recipe has a default value for personal_details.

The test just makes sure the code doesn't break if personal_details is None and case is saved as there's some custom logic on model save. Hopefully it won't break 😅.