No User data showing, exception from Console

My table of users no longer shows me any data:
http://support.backendless.com/public/attachments/01ddeae8a421f55076bc9eac29ca2b0a.png</img>

Notice the error message in the top right:

Could not perform persistence operation: java.lang.RuntimeException: Failed to load RelatedUserDataTableColumn for com.backendless.datamodel.UserDataTableRelation from database

Could this be because I recently deleted a class?

The Users still show up in my app when I run it on the device; just not in the console. This is seriously blocking me at the moment unfortunately :confused:

Could you please let us know your application id?

Mark