Google Wallet doesn’t work with 2D face unlock or screen locks like Smart Unlock or Knock to Unlock.
Make sure that your phone is awake and unlocked.
If this setting is on, you must unlock your screen for every NFC transaction.
Turn off Require device unlock for NFC to make small payments when your phone is locked.
Tap Connected devices Connection preferences NFC.
If Secure NFC is on, then you can only make payments with your phone when your screen is unlocked. If the contactless setup shows that you can pay with your phone but you can’t make small payments with your screen locked, check the Secure NFC setting.
If you can’t find NFC, you can’t make contactless payments with your phone.