Piwik multiple domains - tracking on one but not another

Hi guys,

I have two domains I want to track. One hast ID 1 (www.computerhilfe-eppelheim.de) the other one 3 (klanzeiger.de). 1 gets tracked without any issues, but 3 does not get tracked at all. Both times I use the same piwik installation to track.

I have no idea how such a thing can happen.

any suggestions are highly welcomed!