Go to Google app long press it and tap info>upper right corner tap>uninstall the update and dont let play store automatically update that app , see if its ok ?My Samsung Galaxy 20 is doing the same thing. I used Hey google for years and suddenly it stopped working when I got a replacement phone (the same kind) last week.
I can go into google assistant setup and configure all the settings but once I exit the setup program, assistant turns off. If I don't exit the program assistant recognizes my voice and wakes up when I say Hey Google. ONce I exit it won't and if I go back into the setup I find that .
I've uninstalled Google and Assistant and reinstalled at least twice.
I've checked all of the permissions and the microphone;
I've reset the language to Eng. USA;
I've cleared Google cache and data;
I've uninstalled Google update;
I've restarted the phone several times;
I've set assistant to never sleep;
I've set the battery usage for Google to unrestricted;
I've set and de-selected assistant to wake when the phone is locked several times;
I've checked the app timer for Assistant to verify that it is not set;
I am NOT signed in to a Google Workspace for Education account;
I've retrained the voice model several times.
Probably more that I can't remember right now.
Nothing works. Again, as long as I'm in the setup software Assistant seems to work but once I exit it stops.
Make sure you check all the settings where you can change language/region. There is one in system for your phone settings->system->languages. One in google settings->settings for google apps->search assistant & voice->language and region. One in assistant settings, just open assistant and say assistant settings. Make sure they are all set to the same English(US). You can also try removing old devices in assistant settings, go do devices then remove old devices.