[Client] IP Consistently Shows Incorrectly

This has been a problem for quite some time. The client repeatedly shows that I have more IP than I do. If I log out and then in again it'll show correctly, but until then it'll show an incorrect and higher IP amount. The screencap shows that I have listed 1867 IP, but the Hextech Mystery Champion Shard (1700 IP) does not allow me to purchase it. When I log out and then in again it shows that I have 1522 IP. I have grown pretty tired of this as I've made purchasing decisions that counted on having the correct amount. That's why, for example, I have two mystery champion shards -- which are relatively useless without a third.