What you use as card(visa,mastercard). Don't know if true for you or not, for me there is several choice in card list , For example on some website with the service I use that generate 1 time card for me , I need to choose for example visa or the second option that is blue card.On SE case I need to choose Visa but maybe you are on same case as me with other service.
Also to pay you need your card to be from same country as the one you are to pay. For example you are in UK you need a UK card , you are in USA you need a USA card to process.
Globalcollect when you try to pay check your location with your IP it seem and check the card country or location.