You need to give permissions to your staff to move a tax return online, and delete the online return if required.
This is done in the task permissions in MYOB AE/AO.
Set up task permissions
From the Maintenance menu, select Security > Task Permissions.
Select Tax from the Product from the drop-down.
Select the Group (security group) from the drop-down that you want to set up the task permissions for. The Group Descriptions assigned to the Group are listed in the panel.
Under Group Description, click the plus icon (+) at Maintenance. The list expands and displays a checkbox in the Allow column.
Select the checkbox in the Allow column to give permission to the following tasks
Tax - Migrate return online
Tax - Undo Online Compliance Migration
Click OK to save the changes.
Close and re-open AE/AO for the changes to take effect.
If your changes weren't saved, ensure you selected the correct security group.