Refund Steps:
Visit https://us.battle.net/support/en/help
Click “COD Modern Warfare.”
Click “Payments” (If you don’t see payments, click “I would rather categorize the issue.”
Click “Request a refund” or “Refunds.”
Select the reason for refund as “Tech issues” or whatever you want.
You get refunded.
Refund Conditions:
Did not even start or play the game.
Refund only available for 3 days after you bought it. It seems any play time won’t get you a refund.