Unlisted means it's no longer live but it hasn't been deleted. Unlisted, it will get no views, reads, etc.

With the link below, you can submit a ticket to the help desk. You have to make some selections but at the bottom of all of them is a way to actually submit a ticket without going through forums.

https://help.medium.com/hc/en-us/requests/new

yourfriends@medium.com will do the same thing.