Unable to Purchase Riot Points

I am honestly fed up with the store telling me I have exceeded the maximum amount of attempts when I am trying to buy RP, even when I haven't tried to purchase any today. It tells me to try again in 24 hours, yet when I try again I get the exact same message half the time. I have no idea why it is happening, but I really wish it would stop.

Riot, shut up and take my money. ;n; makes grabby hands at Ghost Bride Morgana