Assign different Domains to different nodes in one Umbraco instance

Question

Currently i have 2 Domains i want to use in 1 Umbraco instance.

1. www.im-tas.de and the
2. www.mainzercarre.de

This is the Node Structure and the domains i want to assign

This is how my hostnames currently looks like for both nodes

this is the imtas configuration

and this from mainzercarre.de

But it does not work. this is the error i get

In my server settings i already assigned both domains to the same folder. i also checked the permission setting but i am not sure.

What i am doing wrong