AegisFX

I'm not exactly great at explaining or troubleshooting but I want to help.
 
Were you only looking at the attk rdr page? I would suggest you have the az/el page going as well. It would help show the sort of "cone" for your radar view.
 
Otherwise:
Radar on
A2A mode
Make sure it's looking at the right altitude.
 
*Are you approaching directly from their 180°? If so, see if things change if you come behind them at a bit of an offset angle. Like having them to your front 1-3 o'clock area.
 
 
Good luck. If you figure it out please let me know 

While I can't confirm, I believe I may have bumped not the recce switch, but the "goggles on-off" may have been bound to a button somewhere.