With the recent update from Android, the Android pay option from Android gear will not work with unlocked mobile phones. From the recent Gear 2.0 release, the unlocked phone will not work with Android pay if the phone has an unlocked bootloader. It is not surprising but either disappointing.
If the user has an unlocked boot loader in the phone,e it doesn’t even allow to add a card from your phone the setup will fail and notify you the system is insecure, even if your wear device bootloader is unlocked too it doesn’t help.As the payment networks are very strict for these sort of things.
The only solution for this issue is, of course relocking the bootloader itself. The bootloader locking will help the user to regain accessibility to the Android pay service. Long story short if you want Android Pay on the phone otherwise, you should lock your bootloader.