Follow the below path to add the enquiry campaign schedule

Admissions --> Campaign Management --> Enquiry Campaign Templates --> + Add Campaign

For example, if the no of days after enquiry date selected as 2, then the campaign email will send 2 days prior dated enquiries

As per the above rule, Today is 05 Nov, campaign message will go 03 Nov enquiries

Note: Please note that the campaign will not reach to cancelled enquiries.