Unable to create a image based host via hammer or Ansible (fam) (api)


I´ve a problem with creating image based hosts using the api.
I tried different options and images but nothing helped.
The Webgui works fine
The only message i get is
"error": {"errors": {"base": ["Failed to create a compute VMWareTesting (VMware) instance centos7-imagetest-119.i.t.t: comparison of String with 16777216 failed\n "]}

Any idea which string this could be or how i can debug this? On vmware i can not see any error related to this.

I´m using foreman-2.3.5