unable to point HAProxy to RabbitMQ services

Question

```ts
[NOTICE]   (7) : haproxy version is 2.7.12-5e21fc9
[NOTICE]   (7) : path to executable is /usr/local/sbin/haproxy
[ALERT]    (7) : config : [/usr/local/etc/haproxy/haproxy.cfg:23] : 'server rabbitmq_back/rabbit1' : could not resolve address 'rabbitmq-main.railway.internal'.
[ALERT]    (7) : config : Failed to initialize server(s) addr.
[NOTICE]   (7) : haproxy version is 2.7.12-5e21fc9
[NOTICE]   (7) : path to executable is /usr/local/sbin/haproxy
[ALERT]    (7) : config : [/usr/local/etc/haproxy/haproxy.cfg:23] : 'server rabbitmq_back/rabbit1' : could not resolve address 'rabbitmq-main.railway.internal'.
[ALERT]    (7) : config : Failed to initialize server(s) addr.
[NOTICE]   (7) : haproxy version is 2.7.12-5e21fc9
[NOTICE]   (7) : path to executable is /usr/local/sbin/haproxy
[ALERT]    (7) : config : [/usr/local/etc/haproxy/haproxy.cfg:23] : 'server rabbitmq_back/rabbit1' : could not resolve address 'rabbitmq-main.railway.internal'.
[ALERT]    (7) : config : Failed to initialize server(s) addr.
```

not sure what i'm missing here? is it somethign to do with how HA resolves the names ?