I can create home and Phone Home page than after some time i can delete Phone Home Page The Error was occur. 1 Undefined page 'My First Module.Phone Home Page' (no page 'My First Module.Phone Home Page'). Property 'Target' of menu item 'Home' Navigation - 2 Undefined page 'MyFirstModule.PhoneHomePage' (no page 'MyFirstModule.PhoneHomePage'). - Navigation -
You deleted your home page and now it is telling you that your target for the home page is missing. So either replace it by another home page or disable the mobile browsing entirely.