Lock Agenda Signups - Checkbox Not Working

I'm the VPE for club 4570.  I am adding some extra agendas to the website, but I don't want members to start signing up for roles just yet.  I am checking the 'Lock Agenda' box on the setup screen.  It is not working.  I check the box and save, and the box stays checked.  But when I close the setup screen and go to the agenda, I see sign-up buttons available.  When I click edit and go back to the setup screen, the box is unchecked.  (See attachment for screenshots)

I saw that someone else reported this issue 4 years ago, but the thread did not show any solution was made.  And the thread was locked so I had to start this new one.

Please let me know if I'm making a mistake or if this can be fixed.

Are you logged in as vpe or admin when trying update a locked agenda? If so you need to get a regular member to check as admin and vpe always have update access.

Yes, I was logged in as an admin.

I did have a member log in and look at the agenda and they confirmed the sign-up buttons were available.  

I just had another member go to the agenda, and she verified that she could see the 'sign up' buttons and it let her sign up for Toastmasters.  

I created the October agendas this morning and on all of them, I checked the box to lock the agenda to keep members from signing up.  On every agenda the sign-up buttons are available.  And a member was able to sign up for a role.

Every time I close the agenda settings window it appears to un-check that box because the next time I go into the settings, the box is no longer checked.

I have updated the documentation to show proof of her signup.  She is a regular member, not an officer or admin.

What browser and version are you using?
What operating system and version?

I will have our programmer look into this.
 

Edge Version 128.0.2739.63
Windows 11 Version 23H2