My ASP.NET MVC authentication sign out shortly – Plesk

I wrote an ASP.NET MVC web site and use authentication. I set a cookie like this

FormsAuthentication.SetAuthCookie(login.UserName, login.RememberMe);

This cookie is created correctly, but user is signed out very soon.

This is my web.config:

<authentication mode="Forms">
      <forms name="LightOilManager" loginUrl="/Customer/Home/Login" defaultUrl="/" timeout="43200" requireSSL="true" />
</authentication>

I don’t know how to fix this. I think it worked correctly in my localhost but I am not sure

I changed the timeout but it doesn’t work.

I checked the cookie in the browser but it was created correctly.

I use plesk and change options but nothing happened