[GAMEPLAY] Future's Market Bug?

I'm playing a game as Soraka support at the time of writing

I have Future's Market as my secondary rune tree

Currently, I cannot buy any items unless I have the full amount in-pocket for that item. The Store prices do not change to reflect what component parts for that item i own

I try to buy Redemption, and you can see i have both of it's component parts. However, although the menu on the Right says 650, the list of items on the Left still says the full 2100 Gold price, and i cannot buy Redemption unless i have 2100 Gold in my pocket at once. It remains greyed out and unclickable even though i have more than enough to buy it

edit when i had 2100 Gold, the game let me purchase Redemption, but only took the actual 650 price from my wallet that it was supposed to be

the game charges me the correct amount, however it won't actually let me purchase the item until i have the total cost in my pocket at once