@ravik6254 I had the same error. I checked the DataTableEditorReport and it looked fine. Then I went to the data class definition and realized it was because of the Keys - I created a property and used that property as my unique Key. However, I put the wrong value in the CAPTION. The caption has to match the property name. And the property name you can find in your data type. For example I have a property name Car Models and the ID is CarModels. I want to use this as the required key. In my class definition, I have to make sure the Key name is CarModels and the CAPTION is Car Models. Once I updated the value, the error went away. Hope this helps.