POST to login callback

Questions API
1

I am using the Okta.AspNet v3 Nuget package in a legacy MVC web app. I need Okta to do a POST to the callback instead of a get. I do not see an option when configuring the callback to do this. Is it possible? Here’s my code:

 public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls12 | SecurityProtocolType.Tls;

            app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

            app.UseCookieAuthentication(new CookieAuthenticationOptions());

            app.UseOktaMvc(new OktaMvcOptions()
            {   LoginMode = LoginMode.OktaHosted,          
                OktaDomain = ConfigurationManager.AppSettings["okta:OktaDomain"],
                ClientId = ConfigurationManager.AppSettings["okta:ClientId"],
                ClientSecret = ConfigurationManager.AppSettings["okta:ClientSecret"],
                AuthorizationServerId = ConfigurationManager.AppSettings["okta:AuthorizationServerId"],
                RedirectUri = ConfigurationManager.AppSettings["okta:RedirectUri"],
                PostLogoutRedirectUri = ConfigurationManager.AppSettings["okta:PostLogoutRedirectUri"],
                GetClaimsFromUserInfoEndpoint = true,
                Scope = new List<string> {"openid", "profile", "email"},        
            });
        }
    }