elavon possible scam letter saying companies are setting up credit cards in my name and using them Knoxville and internet Tennessee Internet

I am wondering if a letter I received from elavon is a scam or legitimate after reading complaints about elavon.

I received a letter from the Knoxville center of Elavon saying that credit cards are being set up in my name and being used.

They report a possible fraudulent charge from ID Railing (apparently non-existent) in Markham ON for over $24,000 dollars.  This is fraudulent if true.  They have sent me an affidavit form to fill in and advise me to report identity theft to the police and to equifax etc.  They have my SIN number (Canadian) and address.

You would think Elavon would verify the company's existence etc. if they want to use elavon's services.  Are these thieves creating credit cards in my name and processing them through elavon's services or what?  I do not know.

So far things seem legitimate, but I began to wonder when I see businesses with complaints about this company.

Is this a rip off or not?  I would like to know before I proceed further.  Are they just phishing for more info from me.