After doing a git pull is it possible you have an error because your Git Token is not valid anymore, here is an exemple:

# git pull
remote: HTTP Basic: Access denied
fatal: Authentication failed for 'https://gitlab-ci-token:YOURTOKEN@gitlab.com/YOURPROJECT.git/'

In order to do the git pull we want to use our credential with the LOGIN / PASSWORD that we use to access GitLab.

Solution 1 : Git pull one time with login (temporary)

# git pull https://gitlab.com/YOURPROJECT.git

Solution 2 : Change the origin URL to HTTPS (permanent)

# git remote set-url origin https://gitlab.com/YOURPROJECT.git
# git pull

It will ask your login and password for the git pull and will not use the git token anymore.