How to Redeem:
Once you boot up the game, make sure you’re on the 'Console' tab.
Log in to your NBA 2K console account using your platform of choice (PlayStation, Xbox, Nintendo Switch or Steam).
Select 'Locker Code' at the top of the screen.
Enter the Locker Code you want to redeem (be sure to include hyphens).
Select 'Submit' and enjoy!
How to check your balance:
On the web, to see your Microsoft account balance, sign in to the Payment options page with your Microsoft account.
On Xbox One, you can check your Microsoft account balance on your Xbox One console without going online.
Select System > Settings > Account > Payment & billing. To help protect your account, you may be asked to enter your password.
You’ll see Payment options, where your balance is shown under Microsoft account. If you have several payment options, you may have to scroll right to see it.
Your current gift card account balance will be displayed.
Abridged terms and conditions:
There are no fees or expiration dates.
Many digital codes from different publishers look similar, and some Xbox games include codes meant to be used at the game publisher’s website instead of through Xbox. Make sure that the code you’re trying to redeem is one supported by Xbox.
You need to be signed in to the Microsoft account for the person who is trying to use the code. If the code was purchased through a different account (for instance, as a gift), be sure to sign in using the account for the person redeeming the code (the one that received the gift).
Some codes can’t be redeemed if your Microsoft account is suspended or has a balance due. Resolve all account suspensions and unpaid balances by going to the Services & subscription section of your account before redeeming the code.
You can only use some digital codes in specific regions. Confirm that your account region matches the region where you purchased the digital code.
Phone and Chat Support: https://support.xbox.com/en-US/contact-us