To edit an added structure, follow the steps below.
Select the cell which contains a structure and click Add/Edit (either on the ribbon or in the context menu) or double-click the cell.
The structure is opened in the default structure editor.
Edit the structure as needed, then click OK to save the changes (or Cancel to discard the changes).
The modified structure is displayed in the cell.
Click the Undo button in Excel (Ctrl+Z) to undo the changes. The original structure is displayed in the cell again.