To request a refund, follow the instructions in this article;
https://support.microsoft.com/en-us/account-billing/get-a-refund-on-apps-and-games-81629012-aa4f-f48b-2394-8596f415072b#id0edf=games_on_a_pc
Or contact Xbox Support through this link;
https://support.xbox.com/contact-us