HAProxy backend CTVL_servers has no server available!

Help!
1

I recently finished configuring HAProxy to balance a service, it has only one node right now, when I check the configuration file I have the correct output:

haproxy -c -f /etc/haproxy/haproxy.cfg
Configuration file is valid

However, I get the next output when I restart haproxy:

[root@localhost]# systemctl restart haproxy

Message from syslogd@localhost at Sep 27 15:36:49 ...
 haproxy[53773]: backend CTVL_servers has no server available!

The logs show me the same messages:

[root@localhost rsyslog.d]# tail -f /var/log/haproxy.log
Sep 27 15:14:41 localhost haproxy[52987]: Server CTVL_servers/token1 is DOWN, reason: Layer7 wrong status, code: 400, info: "Bad Request", check duration: 1ms. 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.
Sep 27 15:14:41 localhost haproxy[52987]: backend CTVL_servers has no server available!

Here is my haproxy.cfg:

#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    log /dev/log local0
    log /dev/log local1 notice
    chroot /var/lib/haproxy
    stats socket /run/haproxy/admin.sock mode 660 level admin
    stats timeout 30s
    user haproxy
    group haproxy
    daemon

    # to have these messages end up in /var/log/haproxy.log you will
    # need to:
    #
    # 1) configure syslog to accept network log events.  This is done
    #    by adding the '-r' option to the SYSLOGD_OPTIONS in
    #    /etc/sysconfig/syslog
    #
    # 2) configure local2 events to go to the /var/log/haproxy.log
    #   file. A line like the following can be added to
    #   /etc/sysconfig/syslog
    #
    log         127.0.0.1 local2 debug

    pidfile     /var/run/haproxy.pid
    maxconn     4000

    # utilize system-wide crypto-policies
    ssl-default-bind-ciphers PROFILE=SYSTEM
    ssl-default-server-ciphers PROFILE=SYSTEM

#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    log global
    mode http
    option httplog
    timeout connect 5000ms
    timeout client 50000ms
    timeout server 50000ms

#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend main
    mode http
    bind 192.168.10.78:80
    bind 192.168.10.78:443 ssl crt /etc/haproxy/certs/haproxyTI.pem alpn h2,http1.1 ssl-min-ver TLSv1.2
    redirect scheme https code 301 if !{ ssl_fc }
    default_backend CTVL_servers

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend CTVL_servers
    balance roundrobin
    option httpchk
    http-check connect
    http-check send meth HEAD uri /login ver HTTP/1.1 hdr Host 192.168.10.96
    #http-check expect status 200
    server token1 192.168.10.96:443 ssl alpn h2,http/1.1 verify none check

I have configured the contexts on SELinux and also checked the ports on the firewall. when I perform a curl it works, so maybe I have something misconfigured or the fact that I only have one server as a backend at the moment is wrong.

If anyone can guide me please, thank you so much in advance.