Can't get kong to connect to keycloak

I’m following this tutorial to secure Kong with Keycloak, I’m doing exactly what he is doing (setting up docker-compose with kong and keycloak, setting them up … ) , except the part where he uses ipconfig, I tried to get my ip manually and used my service name (from docker composer) but I get the same error : accessing discovery url failed: connection refused, anyone has an idea what can be the cause ? I know I’m not providing much details, but I’m new to Docker and Kong and I have no idea where to get logs/details.

Thank you !

P.S. : If you know any other way to integrate Keycloak with Kong, or have another tutorial please let me know.