Have you checked to see if your air ducts are clear and unobstructed. There have been reports of collapsed ducts which could reduce air flow. Going over your rig with a fine tooth comb to find where air is "leaking out" and sealing those culprits will help. Cold air sinks so checking the basement and anything connected to it would be the first place I'd check.
2017 RAM 3500 Laramie CCLB Dually CTD Aisin
2020 3813MS Legacy Cobalt FBP