Hi All,
I noticed when creating a project with the createProjectFromTemplate method, it required the groupWithProjectTemplatesId.
However when having a look into the gitlab docs, group_with_project_templates_id should only be used for group level templates.
For group-level custom templates, specifies ID of group from which all the custom project templates are sourced. Leave empty for instance-level templates. Requires use_custom_template to be true.
Hence the creation of a project from an instance template is not possible and the api call is too restrictive.