Renaming branch from master to main does not work

Renaming main branch to main

Hello, I want to rename the main bran ch in my project from “master” to “main”, but following these instructions here: Rename your Git default branch from master to main (with GitLab screenshots) | Brendan O'Leary

I get an error at the step “git push -u origin main”:

remote: GitLab: You can only create protected branches using the web interface and API.
To https://gitlaburl/my/personal/testproject.git
! [remote rejected] main -> main (pre-receive hook declined)
error: failed to push some refs to 'https://gitlaburl/my/personal/testproject.git'

Do I have to change some settings to be able to perform that command?