Help WiFi Connectivity trouble

[AmeriCanuck]

I'm having a problem with some apps not connecting on home WiFi, but work on other WiFi networks and on mobile data. I've tried resetting modem/router, my device, contacted ISP who told me it's not on their end since they don't block any ports. I did notice at least on my current device (Umidigi Z2) and I think on my Nexus 6P before this, that the security patch is outdated (current device its from May 5, 2018). Anyone have any clues what could be the problem and have any suggestions?

 

[bcrichster]

The newer 5Ghz WiFi spectrum (if applicable to current situation) may not be seem by older hardware only aware of the 2.6Ghz spectrum.. This alone may be an issue as I've run into it on rare occasions as well..