unable to get the first example to work

Hi,
I just started using Backendless and things went smooth until I tried to create the Comment table as per the example here: https://backendless.com/mobile-developers/quick-start-guide-for-ios/
When I run the code, I get the following error:

2016-06-15 22:42:09.318 DemoRegister[76736:4365360] *** Terminating app due to uncaught exception of class 'Fault'
libc++abi.dylib: terminating with uncaught exception of type Fault

This is what I have defined in Comment.swift

import Foundation


class Comment: NSObject
{
 var objectId: String?
 var message: String?
 var authorEmail: String?
}

Please advise on how to proceed.

You must catch the exception using a sync call - or use a call with ‘error’ option. See the samples in this doc.