Connection Refused

I have a .Net Core project running on Docker, and I’ve setup Tyk(on-premise) in the same docker compose together with the .net core projects. I’m able to launch, login and create API in the Tyk dashboard, as well as debug the API successfully from the Dashboard. The Tyk API url that was generated is http://www.tyk-test.com:8080/api/customers. But if i try to call that URL from my .Net Core project via HttpClient request, I’m getting a Connection Refused error. I tried to call the url manually from Fiddler/Postman/Browser and it is successful. Able to advise what am I missing? Tyk newbie here… Thanks!