So hopefully one of the people here will post about the issue. It is a phone connection problem. I think in the phone settings or security, something is blocking the app from connecting properly. You probably know more about it than I do.
I usually get stuff to work by playing with the settings until it opens up. Something new in that S7 is set wrong or protecting what it thinks is a problem. I believe most equipment thinks the MTH stuff is not secure enough to trust. I usually get a warning that I can override it or proceed anyways.
My main problem with the DCS WIFI was drop outs. The phone would revert back to the house's router. So I went into the phone's settings, told it to forget my house router, and made it connect to the DCS WIFI.
Remember the MTH problem displays are usually generic, yet point to what is going on. Again, looks like you know that already.
I get that message from anything like poor signal, engine issues, address issues, etc.