Why can’t this minisplit achieve its setpoint?  I installed a Mitsubishi mini-ducted unit for a client, it was commissioned by  Diamond dealer.  It’s a SEZ-KD09NA4 paired with wireless MHK2 controller.  It works like a champ, except it seems to never make it to setpoint.  For example, today it’s set to 70 degrees it shows ambient not moving from 73.  I verified ambient temperature with another thermometer, the MHK2 is correct.
It’s not a matter of being incapable–by changing the setpoint it quickly acts to raise or lower the temperature.
Of course I suspect that it’s sensing temperature at the unit instead of at the remote.  But I’ve verified that the MHK2 is set to sense temperature at the remote, not the unit.  Is there a setting on the unit that is overriding this?  Does the MHK2 in fact NOT sense temperature and I need a separate remote sensor?  What other settings should I check?