You should not be afraid to contact the agency if you feel as if you have a legitimate case and can fight the detailed quantity. You can tell the collector that you did not authorize the debt and that he is contesting. It is possible that the collector will send a notice, detailing information such as the name of the creditor to pay the debt to the amount in question, and so on. When talking about your information may be stolen, you will not want to leave any step out.
If all else fails - and I recommend this step much - an allegation of fraud. You do not want your information to be used continuously, which means you may have to take some of the more extreme measures. Most likely have a department to speak and a number to contact them. Once you have these bits of information, it is likely to be walked through the process so that every bit of information is used and then you can leave the rest to the services in question.
As someone who has made such a threat or twice in your life, I have to say that there is much more worrying than this case. Want to be able to keep your identity safe and as secure as it can be information. This is not always easy, but that does not mean you're out of luck if it happens. Collection agencies can play a big role in the treatment of debt and telling you what to do if the idea of theft is legitimate.
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