Auto Delete Inactive Forums
Once you signed up for a Free phpBB forum, you can use it as logn as you wish. What we need from you is, "Keep The Forum Active", that is make atleast one post in 30 days.
If there are no posts made for 35 days, your forums get deleted automatically. So, if you do not want your forum deleted, make sure to post at least once within 30 days. Once a forum is deleted, you cannot get it back!