The short answer is that you can't. You can post a message on the profile asking other people to let you finish your work, but you can't enforce a no-editing policy.
Because WikiTree is a collaborative site, when someone adds something to a profile I manage, and if what is added is adequately sourced, I edit the contribution into the style I use on profiles, thank the contributor, and move on. I don't consider these "my" profiles, and I welcome the contributions of others.