vue-router The "next" callback was never called inside of

a navigation guard.

This error message is related to the use of navigation guards in the Vue.js router. Navigation guards are functions that are used to intercept and control navigation to different routes in your application. They can be used to prevent unauthorized access to certain pages, redirect users to specific pages, or perform other actions before the navigation is completed.

The "next" callback is a function that must be called inside a navigation guard to allow the navigation to proceed. If the "next" callback is not called, the navigation will not be completed, and the user will be stuck on the current page.

The error message "The 'next' callback was never called inside of a navigation guard" indicates that the "next" callback function was not called inside one of your navigation guards. To resolve this error, make sure that you call the "next" callback function inside each of your navigation guards.

Here is an example of a navigation guard that uses the "next" callback:

router.beforeEach((to, from, next) => {
  // Check if the user is authenticated
  if (isAuthenticated()) {
    // Allow the navigation to proceed
    next()
  } else {
    // Redirect the user to the login page
    next('/login')
  }
})

In this example, the "next" callback function is called either to allow the navigation to proceed or to redirect the user to the login page if they are not authenticated. Make sure to include the "next" callback function in your navigation guards to avoid the "next" callback was never called error.