After installing Microsoft.AspNet.FriendlyUrls to hide .aspx from URL, The website is showing 500 internal server error only on mobile devices

After installing Microsoft.AspNet.FriendlyUrls to hide .aspx from URL, The website is showing 500 internal server error only on mobile devices, but it works fine on the desktop.

Code in RouteConfig.cs

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.Routing;
using Microsoft.AspNet.FriendlyUrls;

namespace ASP
{
    public static class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            var settings = new FriendlyUrlSettings();
            settings.AutoRedirectMode = RedirectMode.Permanent;
            routes.EnableFriendlyUrls(settings);
        }
    }
}

Code in Global.asax

<%@ Application Language="C#" %>

<script runat="server">

    void Application_Start(object sender, EventArgs e) 
    {
        RouteConfig.RegisterRoutes(System.Web.Routing.RouteTable.Routes);
        // Code that runs on application startup

    }
    
    void Application_End(object sender, EventArgs e) 
    {
        //  Code that runs on application shutdown

    }
        
    void Application_Error(object sender, EventArgs e) 
    { 
        // Code that runs when an unhandled error occurs

    }

    void Session_Start(object sender, EventArgs e) 
    {
        // Code that runs when a new session is started

    }

    void Session_End(object sender, EventArgs e) 
    {
        // Code that runs when a session ends. 
        // Note: The Session_End event is raised only when the session-state mode
        // is set to InProc on the Web. config file. If session mode is set to StateServer 
        // or SQLServer, the event is not raised.

    }

I could Log the error when the website opens on Mobile devices.

This is the error in the log file:

System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.ArgumentException: The relative virtual path 'masterpage/MasterPage.Mobile.Master' is not allowed here.
   at System.Web.VirtualPath.Create(String virtualPath, VirtualPathOptions options)
   at Microsoft.AspNet.FriendlyUrls.Abstractions.VirtualPathUtilityWrapper.ToAppRelative(String virtualPath)