If you have exited Excel after changing the security settings, then re-started Excel and it still won't work then all I can think of is to re-build the Workbook.
In the Visual Basic Editor use File/Export file to export each module, then File/Remove module to remove each module. Then save the workbook.
Re-open the workbook and use File/Import file to import each module in the VBE.
You will then need to reassign each button to the correct macro by right-clicking and selecting Assign Macro.