Thanks for using Syncfusion products.
By default the appointment color can be set by setting the Label of the appointment form. If you are using the “Rooms” as the Label then it will automatically set the color for the specified rooms as the Appointment color. Please refer to the following screenshot,
We need some more information about your query. Please provide the following details, it will be helpful for us to provide the solution at the earliest,
· Whether you want to set the label value for setting the appointment color or you want to override the existing color with the Query events?