Is the IQ Remote mirroring the IQ Panel 2 screen, or is it showing the default disconnected screen?
Did you Master Reset the IQ Remote secondary panel (from the default screen menu in the top right hand corner)?
Have you tried pairing via AP mode?
As a test, Master Reset the IQ Remote secondary, reboot the router and the main IQ Panel 2 (settings > Advanced Settings > Reboot). Once booted up, wait 5 minutes and check to ensure that you are connected to the local wi-fi network.
Additionally, make sure you are on the latest firmware version for the IQ Panel 2. 2.8.1 is the latest.