title: Forms authentication cookie lost when application redirects from another domain to my domain
body: <p>I am creating airlines reservation system with online payment feature. For online payment, I have to redirect from my app to another domain(of another organisation that
  is looking after payment). After payment in successful, another domain again redirects to my app. Another domain is another URL.</p>
  
  <p>The technical flow of my app is: 
  On login page, I have one cookie i.e. __RequestVerificationToken. After login, I will have three - ASP.NET_SessionId, __RequestVerificationToken and 
  247Sewacookie (this is formsauthentication cookie). 
  When application is redirected to my app from another domain, my application will only have one cookie __RequestVerificationToken.
  Two cookies are gone. Therefore, application is redirected to login page since there will be no 247Sewacookie. </p>
  
  <p>Edited later: By the was all cookies are gone and  @Html.AntiForgeryToken() creates new cookie on login page.</p>
  
  <p>I have hosted my app in <a href="https://www.smarterasp.net/" rel="nofollow noreferrer">https://www.smarterasp.net/</a>. </p>
  
  <p>How can I maintain cookie so that user need not to authenticated again?</p>