Compendium purchase: permanent or annual

If you purchase a compendium, is it permanent or only for a year? I assumed once you purchased it you could use it from then on, like tokens and modules. A year ago I purchased the Pathfinder Second Edition Core Rulebook compendium and it has now stopped being available in my games, and game settings no longer show it as available and owned. Have I misunderstood? Does a compendium have to be repurchased each year?

AFAIK all compendium purchases are permanent.  There are limits on the number of games you can share your compendium with though. -Adam

All purchases other than subscription fees should be permanent. If you are not seeing the compendium in your list of owned assets, the best recourse is to file a  Help Center Request . Issues involving accounts are only handled through email and not on the forums, in order to protect privacy and account information.

For anyone finding this in a future search... it has been resolved by the Roll20 Help Centre. The issue: My access to the compendium disappeared exactly a year after I purchased it. According to Roll20 Support my purchase had been refunded and access revoked. I hadn't requested it to be refunded - is it even possible to refund something you've been using for a year!? And I hadn't received any refund. Then on further delving, Roll20 Support said it was a bug. So they reinstated the compendium for me and are going to investigate it further.

My guess is clerical error (probably due to whatever bug they may have mentioned). I'm glad they are resolving it for you.