[GAMEPLAY] Support can't buy full items

I just played a ranked game as sona. Everything went well up until about the 12 minute mark. I started noticing that I wasn't able to buy items even though I had enough money. I was only allowed to buy certain support items, even though I wanted to go damage. Look at my item purchase history. It's a bit odd. I wanted to end up with lich bane and rabadon's deathcap, but could only buy twin shadows and the hextech item. Those were literally the only weapons I could buy.