Hi @Joy1818
Here in the Community Center we can't see your calendar - if you'd like to contact Airbnb Support, you can change the drop-down menu at the top from Community Center to Help Center and open a support query on the specific booking that you're asking about.
One way that a booking for 24 to 26 April can block the calendar from 23 April, is if you selected to have one day open before each booking. If this is the case, you can click on the night of the 23rd on the calendar to unblock it (check the box "blocked because there must be 1 night before and after bookings" to override it for the specific night).
If this doesn't help you can contact the Help Center above.