Operating Natural Ventilation and Night-flushing

When I try to implement both natural ventilation and night flushing in my model, I get this error “1. The simulation has not run correctly because of this severe error: ** Severe ** [ZoneVentilation:DesignFlowRate][C1NatVent0] - Missing required property ‘schedule_name’.”

To make the model more clear, I defined two Honeybee_Set EP Air Flow components one with natural ventilation type as 1 for “window natural ventilation” and the other as 3 for “fan-driven ventilation”. In addition, I defined respective night flushing schedule via Gene Pool with corresponding openingareafractional schedule to make night flushing works only at night-time. Although the model works fine when only Natural ventilation is defined for both EP Air Flow components, I get a severe error when I try to implement different ventilation types. Do you have any suggestions about how I can solve this problem? Thank you for your answers.

I found a similar code on here (image 1 - two EP Air Flow components for opening windows and night flushing): Passive 5 - Schedules - Night Flushing - honeybee-wiki

However, when I run the model with two HB_Set EP Air Flow and checked the resulting idf, I realized that the opening area fraction schedule was “ALWAYS ON” (image 2) indicating that the 2nd HB_Set EP Air Flow component was not taken into account (I defined a schedule named “Night_flushing” similar to the sample code).

I really cannot understand my mistake here. Sample code clearly shows that two EP Air Flow components can be defined for opening windows and night flushing.

(image 1)
(image 2)