Login/Logout button System.UnauthorizedAccessException error

I've seen similar problems but solutions don't apply to my case.

I have a page with a simple MVC Widget in it. Widget's code is quite simple.

When i try to logout using Sitefinity's default login/logout button, i'm getting;

[UnauthorizedAccessException: bu sayfayı ve alt sayfalarını görüntüle' ('Pages') için yetkilendirilmediniz.] DynamicModule.ns.Wrapped_OpenAccessPageProvider_e43ba30d3f5b4564bb781235ba0b116a.GetPageNode(Guid id) +301 Telerik.Sitefinity.Modules.Pages.PageManager.GetPageNode(Guid id) +37 Telerik.Sitefinity.Frontend.Resources.PackageManager.GetPackageFromNodeId(String nodeId) +133 Telerik.Sitefinity.Frontend.Resources.PackageManager.GetPackageFromPageInfo() +703 Telerik.Sitefinity.Frontend.Resources.PackageManager.GetCurrentPackage() +101 Telerik.Sitefinity.Frontend.Mvc.Infrastructure.Controllers.ControllerExtensions.GetKey(Controller controller) +342 Telerik.Sitefinity.Frontend.Mvc.Infrastructure.Controllers.ControllerExtensions.GetViewEngineCollection(Controller controller, Func`1 pathTransformationsFunc) +44 Telerik.Sitefinity.Frontend.Mvc.Infrastructure.Controllers.ControllerExtensions.UpdateViewEnginesCollection(Controller controller, Func`1 pathTransformationsFunc) +26 Telerik.Sitefinity.Frontend.Mvc.Infrastructure.Controllers.FrontendControllerFactory.EnhanceViewEngines(Controller controller) +140 Telerik.Sitefinity.Frontend.Mvc.Infrastructure.Controllers.FrontendControllerFactory.CreateController(RequestContext requestContext, String controllerName) +44 Telerik.Sitefinity.Mvc.Proxy.MvcControllerProxy.get_Controller() +136 Telerik.Sitefinity.Mvc.ControllerActionInvoker.TryInvokeAction(MvcProxyBase proxyControl, String& output) +46 Telerik.Sitefinity.Mvc.Proxy.MvcControllerProxy.ExecuteController() +68 Telerik.Sitefinity.Mvc.Proxy.MvcControllerProxy.OnPreRender(EventArgs e) +39 System.Web.UI.Control.PreRenderRecursiveInternal() +169 System.Web.UI.Control.PreRenderRecursiveInternal() +261 System.Web.UI.Control.PreRenderRecursiveInternal() +261 System.Web.UI.Control.PreRenderRecursiveInternal() +261 System.Web.UI.Control.PreRenderRecursiveInternal() +261 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +6428

Error message is in Turkish. It's "You are not authorized to 'View this page and its child pages' ('Pages')" in English.

I simplified the code to this but still getting the error message.

Controller:
using System.Web.Mvc;
using Telerik.Sitefinity.Mvc;

namespace SitefinityWebApp.Mvc.Controllers

    [ControllerToolboxItem(Name = "CariHareketler", Title = "Cari Hareketler", SectionName = "MvcWidgets")]
    public class CariHareketlerController : Controller
   
        public ActionResult Index()
       
            return View("Default");
       
   


Model:
namespace SitefinityWebApp.Mvc.Models

    public class CariHareketlerModel
   
   


When i remove the widget, error dissappears. I've seen an advice for adding;

Manager.Provider.SuppressSecurityChecks = true;

I've created a PackageManager object and added this to the controller's Index() method but it didn't help. Why is this happening? At the moment, two pages with two different MVC Widgets are giving the same error when trying to logout.