Can't access external service with SDK app

[RaGry]

Hello!
i have a very weird situation with my firewall settings. So to make long story short: i have the centos 7 with nodejs installed where i'm tring to run app with sdk which tries to connect to external service to grab some data (The Things Network Node JS SDK). I've forwarded the port which is used to this connection (TCP 1900) but it didn't helped.
There are two funny things:

1. the same code with the same node js version runs as expected if i fire it on my local computer (no pfsens just regular home router)
2. on the same node js machine i have Node Red running with forwarded port 1880 and it's working without issues.

Also have other services running (like own DNS, Mail server, regular www on apache - where each service is separeted vm and everything behind pfsense) and all forwarded ports are working as expected.

I know that port 1900 is used by uPnP but i have it disabled on my pfsense.

Any ideas? Thanks in advanced!