Voice messages that are addressed to you personally can be found in the call journal under My Voice Messages. Voice messages that have not yet been played are highlighted in bold. The Voice Box button in the function bar displays the number of voice messages that have not yet been played.
The function Clear List delete all entries in the list, including voice messages that have not yet been played. To avoid accidentally deleting a voice message, click on an entry you want to delete from the list and then click on or right-click on an entry and select Delete entry from the context menu.