If the cheat would be detected exceptions can be made for sure. However, seeing you are the only ban report in the last 18 days.
It's safe to assume you got a manual ban. Or something you did while injecting the cheat caused the detection. Maybe not fully following the injection process etc.

Regardless, choosing to buy a year was your decision. Nobody forced you to do it. Could have just bought 1 month to give it a go first.

Unfortunately refunding you means everyone who does something stupid in the game or gets reported too often and gets banned will also be entitled to a refund which is not the case. Rules are rules, they apply to everyone without changes.