I checked the code, and we only update the beginner flag when a non-auto edit is accepted. But it requires that your account is also two weeks old at the time the edit is applied. Your last accepted non-auto edit was applied at 2026-02-23 21:00 UTC (about 6 hours before your account turned two weeks old).
This is a bug (we should at least update the status hourly), but it does mean that you’ll need one more accepted edit in the meantime I’ve went ahead and removed the beginner flag from your account by hand.