One-page-navigation header menu no longer working on new pages

I have a very particular problem with my website http://www.triangleautomatic.com/home.

It is a one-page navigation layout using the main menu navigation menu with #home #products #facility #gallery #contact links in the header. Everything on that URL works as intended.

However I have now added three additional pages to my site in the #gallery section. This takes the user to a new URL and now the main navigation menu header no longer works as intended, because it is now linking to /newurl/#home which doesn’t exist outside of the one-page homepage.

I see it is not possible to have multiple main navigation menus and assign them to different pages of a website. Is there a solution to this problem that would allow me to change how the main navigation menu header behaves when it is on pages other than the one-page-navigation homepage?

Please help.

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