Redeem code couldn't be used

Hi there,

I got a Bonus Content for my NBA 2K20. I went to the redeem page of Microsoft.

I inputted the 5 x 5 characters from the page I got with the game.

It opened a page with multiple games I could use my bonus content, but by accident I closed the window during browsing.

When I wanted to go back, it rejected me saying I used this code already. So I couldn't use it for anything.

This is terribly wrong and it is really worrying me that you if in that moment one cannot select anything the redeem code goes to waste beause I closed that window...

Please help me with this issue!

Thanks a lot in advance.

:)