I set up my own gitlab server on ubuntu vm and I also bought domain from godaddy and link with a record. I can login into registry but cannot push image to gitlab default container registry.

My vm that I am using is behind firewall by cloud provide.

I have tried several method from gitlab document and I am still stuck
https://docs.gitlab.com/ee/administration/packages/container_registry.html#docker-connection-error

I have set config to default except for domain which is gitlab.xxx.xxx

fyi: no nginx installed on my vm