Occasionally, if a shopper is listed on several job search sites, for example Job Slinger, Job Slinger Plus, Shadow Shopper or some of the others, and a company posts on all of those sites, you can get multiple emails in regard to the same job.
Also, if you have established a wide range, say 50 miles and an MSP is working for a client with a lot of stores in the area, say, for example a fast food company with 25 outlets in 50 miles, you can get an email for every McWonderful in your 50 mile range. and if you compound that by the 3 search sites that you are listed with, that may be why you are getting multiple emails for the same MSP. Hope that helps.