Tunneling socket could no be established

I’m trying to use postman desktop app to POST to a REST API. I’m in a corporate environment. There is a proxy configured in Internet Options.
I have tried using the System Proxy, but it times out.
I have also tried configuring it manually with Proxy Auth. However I get: “Could not get any response”. I tried it with the SSL option off and on.
If I look at Postman Console I see "Error: tunneling socket could not be established, cause=getaddrinfo ENOTFOUND [snip]’.
If I try disable the Proxy Auth, then I get a 407 Proxy authentication required response.

I then tried Soap UI and used Automatic settings with credentials and it works.