Ok so this is what happened...
People used to buy ranks with PayPal. When they felt like leaving the server, they asked for a refund. This FORCED Cubecraft to give the money back even though they specifically stated, to NOT refund the ranks. Thus, people would get permanently banned from the store and the server for refunds as they are not allowed.
This caused people to blackmail Cubecraft and mainly the owners with lawsuit threats, so PayPal was removed as a payment option.
Consider using PaySafeCards. Everybody can use them and they're really safe. You can just walk to your local store, ask for a card of 10, 25, 50 or 100 [Your currency] and use the code to pay. Extra money remaining after the payment can be used later, and with other cards.