False responses to site requests through

Help!
1

hello everyone, when checking a site through a haproxy using curl, there are false responses, for example, the site works normally but the proxy responds with a 503 response code, for check I deliberately disable the site and the proxy should respond with a 503 error but sometimes it responds like 200 like everything is fine
Please, help bellow here is some logs from my haproxy :point_down:

Apr 10 04:50:15 haproxy1 haproxy[1917]: 192.168.1.154:6440 [10/Apr/2023:04:50:15.545] frontend_01~ example.com/s2 2/0/1/2/5 200 202 - - ---- 1/1/0/0/0 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:20 haproxy1 haproxy[1959]: 192.168.1.154:6448 [10/Apr/2023:04:50:17.622] frontend_01~ example.com/s2 2/0/-1/-1/3009 503 108 - - SC-- 1/1/0/0/3 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:24 haproxy1 haproxy[23458]: 192.168.1.153:6882 [10/Apr/2023:04:50:24.719] stats stats/<STATS> 0/0/0/-1/0 400 251 - - LR-- 1/1/0/0/0 0/0 "HEAD /stat HTTP/1.1"
Apr 10 04:50:25 haproxy1 haproxy[23465]: 192.168.1.154:6456 [10/Apr/2023:04:50:22.721] frontend_01~ example.com/s2 3/0/-1/-1/3010 503 108 - - SC-- 1/1/0/0/3 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:27 haproxy1 haproxy[1917]: 192.168.1.154:43170 [10/Apr/2023:04:50:27.798] frontend_01~ example.com/s2 2/0/1/2/5 200 202 - - ---- 1/1/0/0/0 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:32 haproxy1 haproxy[23458]: 192.168.1.154:43172 [10/Apr/2023:04:50:29.893] frontend_01~ example.com/s2 2/0/-1/-1/3009 503 108 - - SC-- 1/1/0/0/3 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:37 haproxy1 haproxy[1959]: 192.168.1.154:41422 [10/Apr/2023:04:50:34.953] frontend_01~ example.com/s2 2/0/-1/-1/3009 503 108 - - SC-- 1/1/0/0/3 0/0 "HEAD / HTTP/1.1"
Apr 10 04:50:39 haproxy1 haproxy[23465]: 192.168.1.153:32656 [10/Apr/2023:04:50:39.724] stats stats/<STATS> 0/0/0/-1/0 400 251 - - LR-- 1/1/0/0/0 0/0 "HEAD /stat HTTP/1.1"
Apr 10 04:50:43 haproxy1 haproxy[23458]: 192.168.1.154:41438 [10/Apr/2023:04:50:40.023] frontend_01~ example.com/s2 2/0/-1/-1/3008 503 108 - - SC-- 1/1/0/0/3 0/0 "HEAD / HTTP/1.1"
2

As per:

http://docs.haproxy.org/2.6/configuration.html#8.5

The SC code in the logs:

 SC   The server or an equipment between it and HAProxy explicitly refused
      the TCP connection (the proxy received a TCP RST or an ICMP message
      in return). Under some circumstances, it can also be the network
      stack telling the proxy that the server is unreachable (e.g. no route,
      or no ARP response on local network). When this happens in HTTP mode,
      the status code is likely a 502 or 503 here.