There seems to be a difference between the available Store Credit of yours with the site currency you had picked previously. Would you like to:
Xbox Game Pass Ultimate(XGPU) Top up USD $79.55
Xbox Game Pass Ultimate(XGPU) Top up USD $35.54
Xbox Game Pass Ultimate(XGPU) Top up USD $15.75
EverQuest II (Global) Currency USD $20
Xbox Game Pass Ultimate(XGPU) Top up USD $78.65