[wingnut60]

Take off all plastic vents and check to see if the ducts have come loose, not unknown that this will happen.
Also, the check the AC operation, get a thermometer and put in several of the vents---the best any AC will do is about 20d differential--what ever is going in almost never will be colder than 20d less.
Under the shroud, is the gasket in place along the metal that forms the compartments? You may need new gaskets. Also, sometimes the gasket between the AC and roof has lost its seal, might check that--but you will need to lift the unit to see.
In case you aren't aware--both ACs are connected by an 'H' pattern ductwork, and while the LR AC is mainly for the LR, it will get some air to the BR, and BR to the LR.
In Phoenix in Aug at 110d full shade, both ACs in our '05 had to stay on all day to counter the cooling loss. Shade is necessary most of the time to be comfortable, tho with both ACs on, it should gradually get the inside comfy.
Does one of your ACs happen to be a heat pump? If so, it will struggle to counter AZ summer heat.
Remember, the ACs can do no better than take the inside air and cool it around 15d; if working correctly, this heat exchange will gradually cool the inside down unless you are losing cooling to air leaks and poor insulation. Again, try to find some shady sites in summer?? if at all possible, big difference.
Hope some of this helps.