Some of the tech supports have no clue what they're talking about. Same thing happened to me, first one I got in contact with on Facebook was totally useless. So I contacted them again the next day and got someone who was actually helpful.
@wtv12 That's not true! Wi-Fi Calling works fine on my Pixel 2 XL and I bought it straight from Google. You just have to contact Customer Support and have them enable it for the device.
