Purchases made on Xbox one need repurchasing on one x

Yeah same account I purchased on which is why I don’t understand it wanting me to pay again

Log in to you Microsoft account and go to order history.
Choose option "All available" from the left hand menu and that will show everything that you have ever purchased.
If you then click on the game that is missing, you will get a pop up page that tells you that you own the game and also gives you the option to install it to your devices.
Hope that helps.

Might seem like and obvious question but,
Are you trying to re-download them to your own or to your childrens` XBL account ?
By which I mean are you trying to download it to the account that originally purchased it ?

I have an Xbox One X and the game disc for GTA V. If I want to download the digital version do I need to make a separate purchase?

Long story short, yes. You would have to repurchase it digitally.

Hello Moreizon,

Thank you for your post. All games available on Xbox One will be compatible on the Xbox Series X/S meaning you will not have to repurchase FIFA 21 if and when you purchase an Xbox Series S or X.

I hope this information helps!