Discomfort hours - system 4

Dear all, my building is a warehouse with 3 office areas that, for now, have no hvac system. However, since they are considered a conditioned space, I have to model a hvac system, the same as baseline case. I am trying to model the use of system 4 (packaged rooftop heat pump) in my baseline using Design Builder and autosizing airflow, heating and cooling capacities. However, when using the same airflow, heating and cooling capacities in my proposed design, I get 450 hours of discomfort. I have tried to increase the oversizing of heating and cooling capacities in baseline and using the results in proposed case, but it is still getting difficult to decrease the "Time Setpoint Not Met During Occupied Heating". Does anyone have any idea of what I should try? I am also now questioning if it is necessary to use the same capacities of the equipment and airflow in both baseline and proposed cases. Thank you in advance!