On Postman I successfully posted a request with the followiong parameteres:

When I try to make the request with C# I get an unauthorized error maybe because I can’t pass the key value through the request.

Here’s the code I’m using:

ClientAPI = new HttpClient();
ClientAPI.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("key", "api_token=00000000000000000000000000000000");

I already tried:

ClientAPI.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("key", "00000000000000000000000000000000");

or:

ClientAPI.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("key", "=00000000000000000000000000000000");

but I always get the unauthorized error. I think is because I’m sending this key on the Header but I noticed that, in Postman, the combo Add to is filled with Query Params. If I select Header in this combo I also get an unauthorized error on Postman.

Is this the reason? If so, how do I resolve the problem on C#?