Thank you for the reply. I used the Feedback Assistant to send a more detailed description of the issue (including the app ID).
The envirnonment is pretty much production: I changed the price in App Store Connect and checked on my Mac in the Mac App Store if the price has been updated to the price I set in App Store Connect. I also performed this check on a friend's Mac and on a fresh install of macOS in a VM (to exclude the possibility of caching iessues).