lease make sure that you are not using the DataBind() method to bind the grid. Performing complex grid operations such as Inserting, Deleting, Updating, Hierarchy relations, Grouping, Exporting, Paging, Sorting, Filtering, etc. require accommodating appropriate database operations. Therefore, we suggest you to avoid Simple Databinding and strongly recommend the use of more advanced databinding methods, which automatically handle the aforementioned functions:
Declarative DataSource (DataSourceID property)
Programmatic Data Binding (NeedDataSource event, + DetailTableDataBind for hierarchy). You should set the DataSource property ONLY within these event handler.
That should resolve the issue.