Error entering a Pre-Paid 12 month Live subscription code prior to the end of the previous ...

That shows a billing issue

You need to contact support

You can't use a prepaid code as a payment option it only adds time so if you owe money for a upcoming renewal (remember billing date is different from renewal date and can be the day before)

Hi D.dec,

As already explained by XBF Brad, 36 months is the maximum time for any Xbox subscription on your Microsoft Account. You are getting the error because you state that you currently have 2 years and a few months remaining on your Xbox Live Gold subscription,
and entering another 12 month code would exceed the 3 year limit that was already stated. There is no way to reduce the 12 month code. You would need to wait until you have 24 months remaining to enter the 12 month code.

Or you could take advantage of the GPU discount and convert the 2 years and few months, plus the 1 month you are getting discounted to GPU. After converting to GPU, a 12 month Xbox Live Gold pre-paid code
will automatically convert to Xbox Game Pass Ultimate at a ratio based on the ERP (Estimated Retail Price) of those codes. Conversion rates are subject to change.

The pre-paid codes for Xbox Live don't expire, so you could redeem the code once your current subscription gets to 24 months, but the GPU discount will likely be over by then.

Error code is displayed when trying to use a pre paid Xbox Live subscription code when your Xbox Live gold is still in effect. You must wait for the subscription period to end before you can use the code. Pre Paid subscription codes cannot be used to extend
an Xbox Live subscription, only activate it

Hi there,

Xbox Game Pass CANNOT be stacked like the Xbox Live Gold subscription can with pre-paid codes. Each account can only have one 12 month Game Pass subscription at a time.

Apologies for any inconvenience this may cause. However, pre-paid cards do not have expiration dates so you are able to apply the second 12 month code after the first 12 month cycle is over.

That doesn't make any sense then why this would've happened. When I called to put it onto my account, it kept giving some kind of error code, telling them it couldn't be placed onto my account until after my current pre-paid 12 month live subscription had
ended, so nothing on my end was at fault.