Yesterday, I purchased 400 credits, and used my credit card. Normally when I complete the payment, the credits are instantly transferred, yet this did not happen with the 400. I checked my cards online statement, and it was listed as a temp purchase, and seems to stilll be processing.

I then tried buying 200 credits today with the same card, and it worked perfectly.

Is this an issues with Res, or my card? And any suggestions on what I should do?

Sometimes paypal will put a hold on orders above a certain amount that they deem "suspicious". If you have not received the first purchase 48 hours after you have made it, then you will need to open a support ticket with all the details including the paypal Transaction ID and we will pass the info on to Patrick. He'll straighten it out from there. =)