I activated the Apple TV on us offer but I already paid for a year

I bought an annual subscription for Apple TV in March 2023. 
 

i moved my cell phone service to TMobile in August 2023 and activated the free three months. 
 

It looks like it worked and TMobile found my Apple TV account but how do I get the credit for three months ?  Or will my subscription be extended for 3 months ?

Thanks.