problem with calendar2

hello my name is Max I am Italian
sorry for my english
I have a problem with the management of appointments in the calendar.
I use the library calendar2 version 1.9
this is my problem:

-I write an appointment via the native Android calendar

-I read the appointment through an app written with B4A with the library calendar2 v1.9

-I delete the appointment with the same app written with B4A

At this point I would expect not to see the appointment just deleted, but instead the situation is as follows:
-With the Android calendar appointment is not visible
-With my app the appointment is still visible

I manually free the memory used by the calendar in the settings of the device
Now the appointment is not visible with my app
any suggestions?
thanks