There is a Banner across the Medium Support page stating they’re having a problem.
I noted it yesterday as I contacted them about not being able to use my smartphone any more to write a story in draft.
Here’s the link:
https://help.medium.com/hc/en-us/articles/4903106059159-Mobile-story-editor-feature-deprecation
Which incidentally they responded to very quickly. It stopped in March for those that didn’t know. Not ideal, but at least I know now.
Maybe they put it up in response to you messaging them.