Gitlab api /groups/:id/projects doesn't show all projects

Hi there,

I’m trying to get all projects in a group but there are some missing projects in gitlab api response.
when I call:

GET https://gitlab.com/api/v4/groups/:id
i can see all projects for that group

but when i call:
GET https://gitlab.com/api/v4/groups/:id/projects
there are some projects missing

and i have no idea how to fix this…

any help will be appreciated
thank you