Feedburner Sending Old Feeds

The Feedburner I set up for my Canadian Immigration Consultancy blog is acting up.  A client forwarded an email he recieved yesterday.  It's my post back in April 2012 - A Happy Easter Greetings!  Easter greetings in July?! My Feedburner is sending old feeds! What a shame. LOL

I'm not really sure what I deed wrong.  My guess is that it's because I updated some of my old posts for linkbuilding purposes and published it.  

The thing is, I did not change the date and I have done this in the past without this unwelcomed effect. If you had encountered the same problem and know of a fix to this Feedburner Sending Old Feeds problem, please share. 

I have just Ping my Feedburner feeds and resync it as well.  I hope this will fix this error.