Q: App Purchases

Hey community,

I have been trying for a week to buy gems in clash of clans.

I had the same problem last week but the told me to fix the date and time on my phone, this time I did it but I still have the same problem, it says "your purchase could not be complete" contact apple for support. I do have credits in my Apple Wallet, because I bought an iTunes card with 25us, an I had 5 more dollars before that, the thing that I am trying to buy only cost 20us.

The told me something about the region, I have the store of United States but I am living  in Colombia, and I have bought this things and apps for many years...