While an unlimited number of licenses can be purchased for each account, it's possible you have intentionally purchased less licenses than there are users.
After the Primary User (or initial login created during account setup) purchases the desired number of licenses for the account, the option to set up the Safety Button will appear on all eligible logins. Eligible accounts include the Primary User, Master logins, and Custom logins that have been updated to include the Safety Button permissions. (Refer to the linked article below for instructions on how to update permissions on existing logins and/or create new logins.)
While all eligible logins have access to set up the feature, the number of licenses purchased determine how many users can actually do so. Once all available licenses have been set up in a 'first come first serve' basis (effectively claiming the license upon setup), it will no longer appear as an option to set up for any remaining eligible users.
While the Primary User will be able to override who has access to the feature, the Primary User should not set up the feature if they are not planning to use it, since it will require calling into Support to transfer to a different user.
To override which user gets access to the feature after setup was completed, the Primary User will simply disable permissions for whichever login(s) they don't want to use it. By removing the feature from the login, the license will become available again and appear on all eligible logins until claimed.
Here's how:
Log into the Frontpoint mobile app.
Tap Safety Button on the home screen.
Tap Settings in the upper righthand corner.
Tap Manage Subscription.
Tap Disable next to each login for whom you wish to remove the feature.