Where is the blend door actuator located?

Yeah so that might be pointing to a larger issue with either the control head unit, or the doors needing to be recalibrated, On almost every actuator I've replaced, or in some cases just recalibrated the doors, they would start functioning correctly, but if there's a fault in the system, a full system scan should pick up a trouble code stored in the module, and if the module happens to be offline (not talking on the vehicles network) another module will set a trouble code that it cannot talk to the HVAC control module, so it will be a "U" code which is communications with modules on the network. But just have it scanned at a shop, they don't even have to do the work necessarily, they could just write down whatever codes they find for you, or you could let them diagnose the issue, since they're going to be checking the refrigerant levels and pressures anyway.