Couchsurfing Keeps Asking Me to Pay Again Even After I Bought Membership

Yesterday, I signed up for the app using my Facebook account and purchased the annual membership, but I can’t access the app — it keeps redirecting me to the purchase page again. The annual fee has already been charged to my credit card, and Apple also sent me an invoice confirming the app purchase. However, I still can’t log in.

I’ve been sending support requests about this issue through the Couchsurfing website, but I haven’t been able to reach anyone who can help me resolve it.