When I first got my FE I had the same thing. This is why I mentioned carrier services. Installing that didn't help initially... but after an update in late November or early December, suddenly I had chat features.
Now, the version of carrier services I have (50) caused problems with regular SMS for a lot of people so Google quickly rolled it back to 48 in a subsequent update which I have not installed because fortunately everything works fine in 50 for me. It is possible that 48 does not allow chat services. But if you don't have carrier services installed, it's worth a try.
Also, I am using the beta of google messages. Not sure if that made any difference.