Service Performance Group, Inc. Mystery Shopper Duluth Georgia

I had responded to several surveys online.  I received correspondence from Service Performance Group, Inc. (location 3604 Old Norcross Road; Duluth, GA 30096).  Upon opening the correspondence, enclosed was an assignment sheet and an official check in the amount of $860.00.  At the bottom of the correspondence was a number to contact upon receipt of the correspondence.  I instead contacted the bank the "official check" was drawn on.  Upon contacting the back, since Monday, 14 September 15; I was the 2nd call regarding an "official check" drawn on the back.  The bank representative states they have been receiving multiply "official checks" which are bogus--no good--fraudulent!!!  The bank representative inquired if I had deposited the check--I had not and the representative instructed me to destroy the "official check" immediately.  I then called the number located at the bottom of the correspondence.  An individual answered and I explain to them I have the "official check" verified and that it was fraudulent.  The individual became enraged stating:  "Why did you call the bank before us"--"You called us first".  Then the individual abruptly ended the conversation.  I am aware we are all looking for an extra income somewhere somehow--to stay above the water and possibly keep from drowning for one more day.  I must say the "official check" I thought was a blessing, but it wasn't.