Shortcode protection message overriding not working


I have a membership with id = 4174 and this shortcode on a page:
[ms-protect-content id="4174"]protected content[/ms-protect-content]
I want to override the protection message for that membership, so I go to Membership 2 > Memberships > Edit the membership > Protection messages > Shortcode protection message > Enable the custom message > Edit its contents > Save.
But, the protection message doesn't change.
I granted support access.
The page containing the shortcode is and the Membership name is "Free membership".