Check Line1 and Line2 setting if they are match to your light status
The system uses photocell sensor to monitor the light status by the Line1/Line2 setting. If the lights are on/off when they were suppose not to, the system will send light alerts. You could set the Line2 channel to off if you don't use it.
No need to wire the COM port to the first Quest and It is better to skip the FAN connection, and have the fan and compressor run together through DEHU terminal. If you constantly run the fan and only cycle the compressor, you'll reintroduce water back into air off the wet coil and drain pan right when the compressor kicks off.
PS. Knob on your Quest must be turned fully counter-clockwise and make sure the switch above the knob is on "24V" (external control), not "Dehumidistat" (onboard dehumidistat).
To connect your controller to your App, you need to connect it to the Internet first. Hardwire your controller to your router directly for the most reliable connection. Check the connection symbol on the main screen to make sure the correct connection is built. Use the App to scan the QR code in the back of the controller or the system/serial number page on the LCD screen.