own OBS - trying to remove public repository

version : own OBS (v2.9-obs-server-2.9.5-51)

Hi All,
When someone would like to add a repository in his own project. he sees pretty much all distributions like this :

We do not need all this repository. we have our.the question: would be possible to remove all of them and keep like as corresponding the export mode. >>

Thank you very much,

removing the openSUSE.org project had an effect to remove all distro. OK-.

Now when I would like to add a repository, I get this one :


What should I do to get like the expert mode


Thank you very much for your help!