Free member marked as paid

I have a member who subscribed for one month, then cancelled his subscription. It has been almost a year since they cancelled, but they are still marked as Paid in the admin dashboard. What can cause this, and how can I fix it?

You can check their “Subscriptions” to see if he is still associated with any paid subscriptions.

He is, but it says “Cancelled”. Strangely enough, it also says “Has access until 25 October 2023”, which is in the past. A bug, perhaps?

Strange.
Does this happen to other canceled members?
Can you find any clues in his activity log?

A quick fix would be to delete him and manually add him.