Insufficient client permissions

insufficient client permissions (failed on i_client_needed_permission_modify_power)

Me and the Server Admin are unable to find a fix for these issues

Clients (members) are unable to add or remove groups from themselves despite being able to do it to other Clients.

I have checked all the relevant permissions and they all seem to be set correctly.

I have the ability to do it to myself as Admin and the levels seem to be set correctly for the other roles, just at a lower number, but the roles that they are trying to add to not have any values set for them (vanity)

Ive seen other posts speaking about a skip flag, but isnt this a high level administrative function that creates a security vulnerability? I dont want to allow everyone to skip permissions.