Arrived and discussed issues with tenant. Found indoor and outdoor unit both frozen. Turned outdoor unit off and proceeded to thaw unit. After getting unit on thawed found unit 2 pounds low on refrigerant and also found multiple ductwork restrictions. Added 2 pounds of 410 a Freon to get system cooling better and will be sending an estimate with ductwork repairs that need to happen. Found system is short on return. Docs and supplied ductwork for main floor is restricted by furnace Plenum. Currently have both zone dampers set to bypass air. System has 2-14” supply dampers but only 1-10”&1-12” return duct. The returns need to be increased for the correct cam for the unit size. Bypass damper must be added to correctly control the airflow due to the zone damper set up. System is currently cooling but will freeze up again until air flow restriction ps and bypass damper are corrected/installed