[CLIENT] Shop Overcharged for Champions/Not displaying correct IP

I've had around 8000 IP sitting in my account for the past day or so. Today I decided to buy Twitch, which is priced at 3150.

I now only have 1831 IP left, which means they charged me somewhere around 6300 IP for the champ.

However, when I went to try to and buy Sivir, the shop told me I still had 4981 IP left. So I suppose the numbers are simply not showing up correctly in the IP box.