Problem setting Safari to DuckDuckGo as default browser

Hi all,

wanted to switch from Bing to DuckDuckGo as default browser, made the needed adjustments in Safari -> Settings -> Search (see screenshot) but Bing persists as default browser no matter how often I try, reload, etc.. Why is that? How can I make the change? Should I install the DDG browser extension instead? Please, advise. Thank you!