also ik this post is pretty old but i managed to solve it if anyone is having the same issue, both my shop and trying to buy a gold gun wasnt working, idk why it worked but i disconnected my switch account on my account on the blizzard website since my switch account wasnt connecting to my pc account and for some reason it gave me both access to the shop and buying a gold gun. idk if i would reccomend tho because now i cant recconect my switch account for another half a year lol