5g home internet - phone not autoconnecting..

That didn't do it. I called Tmobile tech support and he hadn't heard of this. We tried creating a new network in the gateway at 2.4g, and it does the same thing.

If I turn my phone wifi off then back on, it doesn't auto-connect to this gateway. And actually it has disconnected itself several times today. It's one floor above me, right above me, and the wifi signal is full strength.

I don't know what else to try, neither did tech support. My laptop is connected to it without issues when I turn the wifi off and on again.