No, it's definitely not correct. I'm not even sure exactly what you are trying to say. It's not clear whether the 'call date' is referring to the email date. And 'find' does not make sense either - if you had it, but don't have it any more. Perhaps: Please refer to the date and time of your previous email. We cannot send you the file because it is not stored for more than 30 days after your call (request?)

"In regards to your email below which was sent 13:45 2 Sept 2013, we were unable to locate your file because our files are only stored for 30 days after your call."