Apple Watch Series 3 unable to update

Trying to update and pair my older series 3 Apple Watch to my iPhone 11 Pro Max. I reset my Apple Watch to factory, downloaded the iOS, and my iPhone is running 15.4.1 so current at this time.

My pairing process works until it tries to download the new iOS into watch and then it says it can’t until I update to the latest phone software. I’m currently UTD so don’t really know what to do.

Please help