I heard this issue was fixed for those who haven't received the hat yet, but those of us who already have the buggy hat weren't compensated with the new one.
I had problems buying cubes at first in the Cash Shop, but after waiting a while I was able to buy them. I'm pretty sure you need to wait for all the Cash Shop data to load (eg. your Cash inventory and Maple Rewards points) before you buy things, or…
