Podcast release date does not show.

I have a Podcast that has been working fine for a very long time, but for some reason all my podcast from mid February are lacking a release date. Due to this, when someone searches for my podcast, they appear out of date. I know that they are at the bottom of the list but it many don't realize that. I have the description with the correct date, but it is automatically sorted by "Release Date".

The Podcast is under:

Harborside Christian Church

Here is my xml:

http://www.harborsidechurch.org/audio/harborside.xml

Is there anything I can do to fix these dates?

Thank you,

Stephen