Hey again Whitey82, looks like Factory Reset Protection's kicked in.
Basically, you'll need to connect the phone to Wi-Fi or put a SIM in, and then you'll need to log in with your customer's Google Account. If the customer doesn't know their password for Google, they should be able to reset that and then login with the new password.
Apart from that, there's no way to bypass FRP - it's a feature designed to prevent phones being stolen, as if they're bricked, they're worthless. At which point you're probably best returning the phone/refunding the customer, or replacing the phone. Either way, give 'em an option. It's Christmas, they're gonna need their phone. Even though the phone's blocked through FRP, the screen and stuff can be used for parts - just not the main board. Swap the mainboard out and you've got a functional handset 🙂.
Tom 🙂