Do you have two different calendars for adding events and for checking the conflicts?
Yess doesn't restrict you anywhere! You can choose different calendars for different purposes.
Availabilityand you will see the below-highlighted sections.
Click on edit beside any of the sections (either
Check these for conflictsor
Add events to this)
You will see this kind of pop-up and there you can select the preferred calendar.
Understand more and better from the below-related articles.