Direct link to page not found on initial load

I am serving up an Ionic4 app on a server and if I go to a page directly the first time, it is not found.
For example, let’s say you went to Before you went to fires back a 404 Not Found.
But if you go to first and try the direct link to login, it works.

Anyone have this problem?

It seems to be happening on sub domains.

Edit 2: Not just on subdomains.

Also, trying to make sure this is not just on my server…
With a fresh app ( angular and with sidemenu ), if I run serve and go to http://localhost:5000 - it works.
But if I go directly to http://localhost:5000/list, I get a 404.

Yet, when using ionic serve: http://localhost:8100/list seems to work. I guess because it is loaded from memory.
How does one implement being able to load a direct link such as: ?