Symptoms
Assume that you are set as a delegate for multiple managers in Microsoft Skype for Business 2015 (Lync 2013). Every time when you sign in to the client, you receive the "You were added as delegate for…" notification for every user who adds you as a delegate, even though they have already been dismissed.
Resolution
To fix this issue, install the April 3, 2018, update (KB4018334) for Skype for Business 2015 (Lync 2013).
Note Lync 2013 was upgraded to Skype for Business in April 2015.
