Why my Gold membership due date not extended after redeeming?

Please head over to commerce.microsoft.com to ensure the code was activated on your account. If it was not perhaps you entered the code on the wrong account accidentally.

If the code was not accepted to your account or you entered it on the wrong account accidentally you should give phone support a call for more assistance. 1-800-469-9269 in North America.

Redeem the code just like a prepaid gold membership card here. Also, you can no longer get founder status as it's way past its due date.

G'day all! Please try to redeem your codes one more time. After that, head on over to
commerce.microsoft.com and look at your purchases and subscriptions. Despite the error, the code redemption may have gone through. If you're trying to redeem Gold memberships, look at your current
membership's expiration date and see if it's been extended by the code you're trying to redeem.

If you still don't see the content from your code on your account, then please hit up
our phone or chat team here for more assistance.

It does say that the gift code is redeemed, but on the console itself it still says the last time it was "extended" was 2 years ago.

double check to see when the subscription ends.

when I've used a code to extend my Gold/Game Pass/Ultimate Game Pass it hasn't changed the date for when it was last extended as that date is for when a charge was last made against a credit/debit card.

if you redeemed the code and it all went through, all you would see is the expiry/next charge date change to reflect the extended time.

Yes, they are cumulative. You can stack Xbox Live Gold time for up to 3 years (36 months). You can redeem all three cards and it will extend your Gold membership for 18 months.