What antenna are you using?
Also to be quite honest i don’t know what the “pre-programmed” part means in the dongle description.
Two “nano” sized SDRs, 1x pre-programmed for Stratux 1090ES, 1x pre-programmed for Stratux 978 MHz/UAT. Does not include antennas.
New : Now with updated R820T2 tuner.
(https://www.amazon.com/Stratux-1090ES-UAT-Radio/dp/B01ENU1DQC/)
So i’m not sure it’s receiving stuff at other frequencies.
You could do a spectrum scan, that should show you if it has some kind of filter or is specific to a certain frequency.
(Do I Need A Filter?)