I am currently working with resource reservation calendar (with content approval) on SharePoint 2013. The user will request an event and submit the list item, and an approval workflow will kick in, which allow admin to approve / reject the request. That condition works great.
The issue is, when a user submit an event for specific date (lets say August 3rd, 2017 10:00AM), and the request is rejected, another user would not be able to submit another event at that date and time, since the Check Double Booking will prevent user from submitting.
Is this behavior is a behavior by design? For now, since there is no option to add custom code (event receiver or similar solution), one of the option that comes to me is to delete the event each time admin reject the request.
Any other better solution for the case above?