Either a Docker Compose project or a Docker Swarm stack. It depends on whether docker swarm is initialized or not.
I should know more about your environment to tell you more, so here is some guesses.
1 ) Containers in a Docker Compose project have labels like
If you have a container which has some of the labels but not all, it might confuse Portainer. For me it is enough to define “com.docker.compose.project” so this is probably not the case.
2 ) Somehow your docker stack became hidden. Portainer 2 has hidden container feature in settings. If all of your containers are hidden in a stack, you won’t see the stack itself in Portainer.
3 ) You have a stack with the same name but you don’t have permission to see it. When you create users with access to the environment they will only see stacks assigned to them or created by them.
4 ) You have a stack with similar but somehow invalid name which was normalized and became the same behind the scenes
(Ui: Sorry for not using the standard “numbered list” but using that the numbers disappear.)