Hi Edmund,
Thanks for using Syncfusion support.
The dashboardPath you have assigned to the API is should be accessible on the machine where the service hosted to. Inaccessible dashboardPath over the network where the hosted service on local towards the remote will leads to the issue “The requested dashboard file was not found”
Changing the accessible dashboardPath with respect to the hosted service will fix this issue.
And please let us know if you need further assistance on this.
Regards,
Bharath N