Problem with SPA/route on PHP site

Hi I got a problem with SPA and route I have a testsite that is working with route and this is it
https://tester.howden.no/

If I press the menu “Andre” I get the right response …

https://tester.howden.no/andre

But the problem is when I press F5 or refresh the page I get a 404 error.

I have tried the “links relative to” “site root” but it doesnt change anything.

Any ideas is appreciated.