Finally figured it out! I had two linked microsoft accounts, one was logged into the browser and the other was logged into the MS store. Usually in the past I've never had issues and it had run seamlessly but for this it wasn't working. I had put the balance on one which made it inaccessible to the other... Had to change account on MS store before it would let me pay via balance.
Thanks for this, ill give it a try now
Mentioned here bud. I use a Mac so assumed it was greyed out for me for that reason. Read the quoted instructions bud, that should sort it :)
Hey @BuzzDuraband , im used to using this method for xbox and do so using a browser. This will be my first time using this method with a WIn10 game, when I click the link and try to click buy it basically says not available on my device. What am I doing wrong? should I be using the Microsoft store app on win10 itself?