ConnectHome Connectivity Issue / WiFi and SmartThings

I’m experiencing bizarre connectivity issues with my Samsung setup: 3 ConnectHome hubs used for both WiFi and SmartThings. For device control, I use the SmartThings app, not the Connect app.

When my iPhone connects to the primary hub (plugged directly into the cable modem), no issues. However, when I move upstairs and my phone migrates to a different Connect hub, the issues begin. My phone indicates continued WiFi connection – strong signal, looks perfect – but I actually have no connection whatsoever, nothing works (browsers, other apps, etc). Also, all of my devices show as disconnected in the Connect app, and everything is inaccessible in the SmartThings app. If I switch my phone to the guest network, everything returns to normal: phone has internet access, and both apps show everything. (If I switch back to the primary network, everything stops working again.) Also, instead of switching networks, if I reboot the two sub hubs, then I can use the primary network and everything works fine.

In case this helps … I am using the same network name as my previous router, but I changed the password intentionally to require new setups in all of my WiFi devices. I did this, in case the security encryption or some other protocol changed from the old router to the ConnectHome. I went through all of the setup, and everything works just fine … until I switch hub connectivity as described above.

Any help would be appreciated. Thanks.