Hi Khusan,
Thanks for your interest in using Syncfusion products.
We have provided support to dynamically edit appointment collection (add new /remove appointments) in Schedule control. We have already logged an issue with “Application hangs when appointment collection is added dynamically in VisibleDatesChanged Event” in Xamarin.Forms (Android). Is this scenario similar to yours? Could you please ensure whether the issue reproduced with Xamarin.Android or Xamarin.Forms Android? It will be helpful for us to further analyze on your requirement and provide you possible solution.
Regards,
Swathi G