Refunding

[S4fikiller]

I noticed two things about refunding
First observation I noticed was the system only allow me to make one refund per prepaid card I have
Second observation I noticed was when I card an item with a visa then refund the funds back to a Mastercard they block the card im doing the refund for
In both instance they block both methods #1 after I successfully get a refund it will never let me use that card again & When I use a visa to card with then try to refund back to a Mastercard my Mastercard gets blocked
Any helpful advice on possible what Im,doing wrong