"The macro cannot be found" when clicking on the ribbon

[nickgearls]

In Powerpoint (Office365, v18.2110), I created a ribbon button like this:

<mso:button  id="updateProperties" visible="true" label="updateProperties" imageMso="RecurrenceEdit" onAction="updatePropertiesCallback"/>

In my VBA project (where all macros are working), I added the callback:

Sub updatePropertiesCallback(control As IRibbonControl)
    MsgBox "test"
End Sub

When I click the button, I receive the following message:
"The macro cannot be found or has been disabled because of your security settings"

Any idea?
Thanks a lot