Currently clicking notifications for recommendations (new missions, new exercises) does not result in being redirected to the correct page.
The issue has been reported to the technical team. As of now we do not know when the problem will be fixed. We apologize for the inconvenience. Recommendations for new exercises will be visible on the mission page, though.
If you should see problems with links in notifications for other issues, for instance, badge notifications not taking you to the badges page, please click the Report a problem button in the Help center and file a Help request ticket about the matter.
Internal ticket: 228265712828784
Dec. 20th 2016