Just to be sure we explain how the push notifications work, let me give a bit of background. In recent years there has been a push for increased security from browsers, which comes in the form of browsers like DuckDuckGo, or add-ons to other browsers that block trackers and cookies. The message for signing up for notifications is based on cookies. If you regularly clear your cookies, or use a browser that blocks them, you'll always be prompted to respond to the question, since the site has no idea if you've already given an answer, if it doesn't detect that answer in a cookie.
If you're not blocking or deleting cookies, this is probably a bug, but we'd need to work with you to get a lot of technical details to see where that leads us. If that is the case, let me know and I'll ping you directly with some additional questions.