[CLIENT] Champion purchased at double the price [IP]

Earlier today I had just under 11,000 IP, after looking through all the champions I did not own I decided to purchase (3150 IP), in the purchase confirmation screen it told me would still have over 7,000 IP after the purchase after processing the purchase my remaining IP is down to 4,373, the client appears to have charged me twice for a single champion, so i took a look at my purchase history and it shows only 1 purchase was made today, the previous purchase was made Christmas eve when I purchased the Debonair skin.

I would like to try to purchase another champ and confirm what is happening, however I do not wish to loose anymore IP as I was saving them for rune purchases, and I only have 1 refund left. Please look into what has caused this bug, and return to me my missing IP.