I am sending faxes, and try to get notifications using callback post call, like this https://www.interfax.net/en/help/callback
I setup a web page on my web application, and listen to post call, parsing the form data posted to the post call.
I tested the page on many http client testers like CocoaRestClient on mac, and fiddler on windows, and curl in unix.
And I changed my settings to have the settings: "Web feedback URL" to be that url, with setting to always send the confirmation
and I am sending faxes , and waiting that the fax was sent from by looking at the web page.
But I am not receiving anything on the url