I have realized the memberships are not expiring, it has been like this since april:ish.
I have checked om my dev sight as well (localhost). Previously we had an error in the logs with one of memberships cron jobs. I think I have an open ticket with this, in connection to slow site. I dont know if this is the same issue.
I dont have it in the logs anymore and I dont have logs for more than a week. So I dont know when it disapeared.
Here is an image of one user, 4 of her memberships is stil active and it is a lot of days since they expired.