Sub menu, page not found

I created a sub menu, but now the original page does not work and the sub pages are showing in the menu, but when you click on them, it says, “Oops, page not found”?

Hello there,

Please avoid using the services for your pages permalink structure as it is already associated to the services post type (Dashboard > Services). I would like to suggest you use our-services.

Regards,
Kharis