Can my Apple Music gift card transfer to my new iPhone 12 if I already redeemed it on my old iPhone 8 (if not) how do I get the money to transfer to my new phone for Apple Music.

I recently got a new iPhone 12. My previous iPhone was an 8 and I put my Apple Music gift card into my old iPhone 8 around Christmas before I recently got my new iphone in the beginning of January, how can I tell that the money transferred into the new iPhone 12 for another month of Apple Music.