Frequent Disconnection on 5G Home Internet

As far as other responses, I too have the exact same problem with my 5G gateway, the Arcadyan KVD21.  It's in a window facing the direction of the tower as located by the app, and when working, has 4 bars and reports "Very Good Signal."  It is plugged into a wall outlet via a 6 foot 3-prong extension cord (14 gauge).  Nothing else is plugged into the outlet.  It works fine most of the time.

However it tends to cut out at night when I'm asleep.  I wake up about 3am and it's off again, the time of the very least area demand.  It does not often cut off while I'm using it.  I haven't noticed any lagging or slow responses when it did drop the internet while I was using it, it just went dead.  I  Just finished building a cooling fan base for it, and sealed the fan to the bottom of the gateway.  The fan is a 12 volt computer fan 4.75 inches square, so a perfect fit.  It is raised up on (4)  3/8" feet.  There was substantial airflow from the fan at 9volts, and no noise like there is at 12 volts, so I used an old 120vac to 9vdc adapter.  I notice hardly any air coming out of the tiny holes in the gateway, but am trying it.  The cabinet used to get warm (not hot) but now is cool to the touch.  I rigged up an indicator switch to both control the fan and provide a blue LED when running  I'll let it run and report back if it drops the internet again.