Have you tried the full 60 second reset as below;
Remove any ethernet cables from the Hub and hold the pinhole reset switch for 60 seconds. Do NOT reboot the Hub, just let it do it's thing. Note you will need the passwords from the bottom of the Hub afterwards, so make sure they are legible. NOTE this will remove any custom settings you may have set in the Hub, and they will all have to be setup again.
Also for the Wifi check as below;
• Access your Hub by navigating to 192.168.0.1
• Login with the default login info (on base of Hub) unless you've already updated it.
• Go to Advanced Settings > Wireless > Security
• Disable the Smart Optimisation on the wifi bands.
• Under Wireless Frequency 2.4GHz change the Wifi Network Name (SSID), suggest append _2 to the end.
• Repeat for the Wireless Frequency 5GHz, suggest append _5 to the end and click on Apply changes
• Try to avoid spaces and periods in the SSID names as they can cause issues with certain devices.
Failing all this, it could be the Hub is faulty and VM will need to send a tech to sort it out.
As for the app, don't install it if you want to keep a split SSID, it has been known to reset Hub's to suit VM's Intelligent Wifi.