How to deny HTTP from IPs other than those allowed by multiple ACLs on HAProxy?

Question

I'm trying to deny access to my HTTP server from IPs other than those allowed by my subnets ACLs on HAProxy.

I have the following HAProxy configuration :

frontend http bind 0.0.0.0:80 acl 1st_Floor_ACL src 192.168.0.0/24 acl 3st_Floor_ACL src 172.16.0.0/24 acl my-webserver_ACL hdr(host) -i my-webserver_ACL.myDomain.com use_backend my-webserver if my-webserver_ACL backend my-webserver mode http option forwardfor except 127.0.0.1 server my-webserver 10.10.0.0:80 maxconn 5000 check 

In the frontend section, I tried replacing this line :

 use_backend my-webserver if my-webserver_ACL 

by these two lines :

 use_backend my-webserver if my-webserver_ACL 1st_Floor_ACL use_backend my-webserver if my-webserver_ACL 3st_Floor_ACL 

and reloaded the haproxy.service.

But it does not forbid other IPs.

Can you help ?