There is a newly created Multi user field `Usersss` in the Leads module (`sss` is an exaggerated typo):

Now I fix the name to `Users`:

And also fix the API name in Setup > Developer Hub:

This vaguely reminds me of a similar issue with api field renaming in linking modules.

It's also strange from a data structure perspective, that the field is nested, i. e. it's there twice: once `Users` and second time `Usersss`.