Q: Can not download this episode on Apple Podcast App

One of our recent episodes, which is very popular no longer can be downloaded on the ITunes Podcast App on my iPhone.  The file has been downloaded over 5,000 times already and now it does not play.

It does work on the RSS feed and on iTunes Desktop version. Why would it no longer be working on the Podcast App? 
Is there something we can do to check this?