Issue: Player was purchased 32 iron blocks and went to purchase a second 32 iron blocks but did not get the second 32 blocks. What they did was they had the first 32 iron blocks in hand then clicked with the second 32 iron blocks with the intention to stack it but somehow 32 blocks disappeared but the cost was removed from their inventory. 

Priority: High 

Location: This occured at spawn shops

Steps to reproduce: I purchased 32 iron blocks (from Zuoers shop) and then with that 32 in hand tried to purchase a second 32 but instead of 64 iron blocks I only had 32 but payment for both stacks was taken. I tried it again at a different shop bought 32 warped fungus (from ooga's shop) then with those in hand try to purchase a second 32 warped fungus and again instead of 64 warped fungus I only have 32 but payment was taken. I further tried it with a full stack. I purchased 64 watermelon and with them in hand try to purchase another and it would not let me so it only happens for items that can be stacked.