Cache folders with and without "www" – both have different versions

In Kirby’s cache folder I get two folders, site/cache/domain.com and site/cache/www.domain.com. If I make changes in the panel, the cache gets saved only in site/cache/domain.com. So if I visit the website with “www” in front of the domain, I get the old version of the website – without “www” I get the new version. How can get both versions synchronised? Thanks a lot for any tip!

You should not serve the site under two different URLs (duplicate content), but one domain should redirect to the other, either www to non-www or vice versa.

Thanks a lot, I found a wrong setting in the hosting ! Now it works