GitLab Repository Pull Issue Resolution

I'm currently facing a significant issue with my GitLab repository; I can't pull code. Every time I try, I receive an error message stating "project doesn't exist." Despite my best efforts, I've been unable to rectify this issue myself, hence my need for a knowledgeable freelancer. Your task will be to assist me in resolving this error through AnyDesk.

The ideal candidate for this project will have:
- Strong experience with GitLab,
- Proficiency in troubleshooting GitLab authentication errors,
- Ability to patiently guide me through the resolution process via AnyDesk.