Profile > Chat 500s

My account on i2p.online 500s when visiting https://gitlab.i2p.online/profile/chat_names. I just reproduced it by:

Creating a GitLab group with Mattermost team
Creating a project in group
Enabling Mattermost integration for project
Deleting project
Leaving Mattermost team
Deleting GitLab group
Creating a new GitLab group (with different name) with Mattermost team
Creating a new project in new group
Trying to enable Mattermost integration for new project, which succeeds, but then redirects to Chat page which 500s