alarm + lights help, quick plz Options

[Celicaca]

so i got my alarm installed. when the parking lights or headlights are not on, and i unarm/arm my alarm, the lights flash as supposed to. when my alarm goes off, the lights flash also.

BUT when my headlights are turned on (like when u keep ur headlights switched on and you remove your key and exit the car, they turn off) and i arm or disarm my car, the lights do not flash; same as when the alarm goes off

so what i want to know is what the installers did wrong exactly and how to correct it because it makes more sense for the lights to flash @ night (when the headlights are on) rather than in daylight (when they are on the off position)

if someone could respond by tomorrow morning id be very grateful, thanks