ASP.NET Facebook Login GetExternalLoginInfoAsync Always Return Null

Question

I have a ASP.NET MVC application. I integrated it with Facebook. It works but here is a strange problem. If i open a incognito window it works. But it not works in normal window. Could there be a cookie problem or?

What's your suggest?

//loginInfo is always null except incognito window
var loginInfo = await _authenticationManager.GetExternalLoginInfoAsync();

if (loginInfo == null)
{
    return RedirectToRoute("UserLogin");
}

Answer 1

It seems that there already exists a local cookie containing authenticated information in the browser. It is recommended that we clear the locally stored browser data before testing the logic, and thus try it again.

Feel free to let me know if there is anything I can help with