# Negative matcher is not working - error while parsing rule ! is not supported

When I try to negate Host matcher in router with "!" operator (which is documented here Routers - Traefik "Invert a matcher") i get an error:

"error while parsing rule ! is not supported"

My rule is:
`traefik.http.routers.my-host-traefik.rule=HostRegexp(`{subdomain:.+}.my.host`) && ! Host(`traefik.my.host`)`

Traefik version 2.5.6

What i doing wrong?

The error might come from elsewhere.
It works fine with me with this configuration:

``````version: '3.6'

services:
traefik:
image: traefik:v2.6
command:
- --providers.docker
ports:
- "80:80"
volumes:
- /var/run/docker.sock:/var/run/docker.sock
whoami:
image: traefik/whoami # https://github.com/traefik/whoami
labels:
traefik.http.routers.whoami.rule: '!Host(`whoami.localhost`) && PathPrefix(`/`)'
``````

Thanx for testing. I realized whats wrong, I have another one traefik, but version 2.2.0 which is not supports "!" operator