The DELETE endpoint is deleting all vertices and not just one

Using this URL:
http://myIP:9000/graph/wtapp/vertices/ConceptItemContent?where=id=E3605013-5183-43E3-A57E-52D0F7703C27

All ConceptItemContent vertices are being deleted and not just the one with this ID. This vertex also uses the primary Id as an attribute.

Any idea what I’m doing wrong?

Thank you