RC Willey Home Furnishings RC Willey Home Furnishings wrongfully reported me to the credit agencies, dropping my score Salt Lake City Utah

So I went to check my credit report in April and found a collection from RC Willey for $500. I called RC Willey the company they say it is a debt from 1999 for tires that I purchased. I never purchased the tires. I asked them to send the documentation showing how, when I purchased the tires with the amount,the signature, etc. I was told it would take some time to get that information. It's been longer than a month what's my next step? FTC,FBI, State Attorney Generals or TASC. If they just put it on my credit report why does it now take so long to send me the documentation. This has to be identity theft so what else do I have to do. I've never been to Utah, but that doesn't mean RC Willey is the original debtor. Help me Please.

Amy
Gainesville, Florida
U.S.A.