I have created a custom flow and used the subflow but I am getting the flowing error (Error element Get_Slots (FlowActionCall).
An Apex error occurred: FSL.Exceptions.GeneralException: Script-thrown exception)
When i view the debug log it appears everything is working, so i'm not sure what i am doing wrong. I am using the flow scheduler from this site below. https://unofficialsf.com/flow-scheduler-enable-self-service-scheduling-for-field-service/  



Here is how I have the subflow setup