Cannot access / install addons from Kodi repository

Hi
I have Kodi 16.1 running on a raspberry pi 3.
Kodi was installed from retropie.
In Kodi when I try to access the Kodi repository I get a connection error.
I also cannot install any skins as there is no “get more” button in the skins settings.
I have searched the net and forums, but cannot find any solutions that work.
It looks as if Kodi has no network connection, but it’s definitely connected as youtube works 100%
Youtube was installed “manually”.
Any help would be appreciated.