Hi Johanny,
Thank you for contacting Syncfusion Support.
We suspect that resource id type has mismatched in your data base appointment collection and controller resource collection which may cause the reported issue “appointments not showing in scheduler”. We have prepared a sample for your reference which can be downloaded from the below location.
The type of resource id should be same as below in your db and controller.
Kindly check the above scenario in your sample if the issue persist still kindly try to reproduce it in the above sample and revert us.
Regards,
Nevitha.