I've been wondering the same thing.Got used to use "Hey Google" to launch google assistant on S7 Edge, now find that it's not available on S9+.
Is it available on some Carrier network now or it has not happened to any S9 or S9+?
Are you aware of any such setting?I use "ok Google" without any issues. Maybe in the assistant settings just change your launch phrase?
Are you aware of any such setting?
Also it only works from the lock screen if you updated to Oreo.
Today just got an update July security patch (Sprint) and Hey Google is now an option along with much improved Samsung Stock text app.
What are the improvements to the stock text app?