Show service resources by Availability

Hi , 

Can someone please help me with the below question:

Service resources on Select Service Resource and Service Appointment Time Screen are not displayed by availability though flow attribute Show service resources by Availability is set to true.

According to the salesforce documentation, flow screen attribute Show service resources by Availability indicates whether service resources are sorted by availability, with earliest available resources shown first.

I have set this value to true ({!$GlobalConstant.True}). But service resources on  Select Service Resource and Service Appointment Time Screen are not being displayed by availability.

Please see attached screen shots

Thanks.