301 redirect only works with www. in the url

I have a clients website on devoorzieningenwijzer.nl
They have a separate webapp on app.devoorzieningenwijzer.nl.
I have a few 301 redirects setup that redirect devoorzieningenwijzer.nl to app.devoorzieningenwijzer.nl. (and also the folder structure after the /)

See this image:

This all works fine when you go to www.devoorzieningenwijzer.nl/apps

But when you go to this url WITHOUT the www in front of it, you get a 404 page not found. See this image:

How to fix this? because a lot of people don’t use www.

(I already tried changing te default url in the webflow settings. This does not do the trick.)