I have the exact same problem. Changed password in app to no avail.

Last build for the M9+ is 20190926. Any hope on getting an updated fw with uPnP settings soon?

Tried to set my M9 Plus as main router, but had to switch back to AP mode and reconnect my ISP's router to get IPTV signal back. There is no way to check IGMP status in the app, I really miss...