Why can't the fees be changed in a return?

In the Fee Summary in a tax return, if you are attempting to change the fees but they revert to their previous values, there are three reasons why that can happen:

• The return has been marked complete. Once a return is marked as complete, the fees are locked and cannot be changed unless the return is unmarked as complete and put back to the "In Progress" status by a preparer with a security role including this permission. 
• The return has been transmitted. Once transmitted, even if the return is rejected by the IRS, the fees cannot be changed.
• You do not have permission to change fees based on the role assigned to you.