Can't Buy Rp :(

Im having this problem for several of days now, every time i try to purchase RP it always gives me this error "You have encountered an error, please try again later" i tried to lower the thingy in IE to medium and i still have the same problem, sent a ticket to riot support but still no response from them, im using a Visa card and i tried to buy things from other games (WoW, Hearthstone and Steam) and they all worked fine exept league of legend. I really need to get RP so i could transfer my acc and get the new ultimate lux skin :(.