Nav item issues Swift

This is a quick and simple project for the right person.

Using WKWebView - navigation controller, loading external url.

I have the correct button items in the nav bar on home page.
The correct item buttons on first click (changes to back button)
Returns to home page on click of back button or swipe right.
Returns to correct items in nav bar.

Issue is when more than one click is made from home page. Subsequent back clicks lose the back button and return the button from the Home Screen, even though not on the Home Screen.

Budget reflects the size of this project/fix.