You may find yourself in front of a Gitlab install and completely forgot the password.  The following method works flawlessly, so I haven’t changed any of the steps.

To reset your root password, first log into your server with root privileges.

Start a Ruby on Rails console with this command:

gitlab-rails console -e production

Wait until the console has loaded.

There are multiple ways to find your user. You can search for email or username.

user = User.where(id: 1).first

or

user = User.find_by(email: 'admin@example.com')

Now you can change your password:

user.password = 'secret_pass' 
user.password_confirmation = 'secret_pass'

It’s important that you change both password and password_confirmation to make it work.

Don’t forget to save the changes.

user.save!

Exit the console and try to login with your new password.

Source(s)

• https://docs.gitlab.com/ee/security/reset_root_password.html