Thanks for contacting PUBG Support!
I understand that you wish to know the refund request procedure. I am glad to explain you the procedure. Did you know Battlegrounds are refundable if they meet the steam refund criteria with the 'Steam Platform' game. Steam game refund conditions are as follows.
1) Within 14 days after the initial purchase of the game
2) If a) is satisfied and gameplay time is less than 120 minutes
3) If you meet 1 and 2 and do not request excessive refund
You can request a refund in the condition that you meet the three conditions. It takes one week to request a refund according to the steam condition. If you choose to refund your Steam Wallet, it will be done within a relatively short time.
Please note that you may need more refund time than expected because the steam platform is located overseas.
If you have any other concern please let us know.