Dec 12, 2019 10:05 AM|PatriceSc|LINK
This is a bit why I suggested an outdated but simple approach as depending on what you are trying to do the whole process is not that easy. For a POST it would be rather https://docs.microsoft.com/en-us/dotnet/api/system.net.webclient.uploadstring?view=netframework-4.8
You have also https://stackoverflow.com/questions/13039068/webclient-does-not-automatically-redirect
They could also check the user agent (you can then change that) to prevent automating their web page.
Depending on what it does, check if they don't have an API. I always favor using an API over "browser and/or http automation" (and try to refrain otherwise as I consider the absence of an API as a will to NOT allow consuming this "service" programmatically).