Connection refused response from container with opened port

I have a container which is listening on port 8080 on network called “bridge”. From another container from the same network when I tried to curl it, I’ve get “Connection refused”.
When curling from inside container where port is listening, I get proper response.
Service was warking on different backends (h2o, http-server), same problem.
The funny think is that, that port is accessible randomly.

Few moments later on next curling I get “Connection reset by peer” and with another request I get successful respone. Didn’t change anything.

Minute later after last edit, again “Connecion refused”.