My suggestions is to dispute the charge with the CRA. Write to which agency is reporting it on your credit....
When they respond, they need to give you more details. They usually will.
If you are blessed to reach a real live person at the CRA, they may be able to tell you more information over the phone about who is trying to collect.
Welcome to the forums!
This looks like it might be a medical collection. Have you pulled your free credit reports freecreditreport? Reports from there will have the most information.
Once a CA posts to your CR, that is an intitIal commumication that requries them to provide dunning notice to you wth five days, and to post with the CRA their DOFD within 90-days. FCRA 623(a)(5)(A).
They are requried, in their credit reporting to the CRA, to provide their address.
If you dont have a CA address, file a dispute with the CRA of their posting under FCRA 611(a)(1). Also include in that dispute a request under FCRA 611(a)(6)(B)(iii) of the procedures used by the CRA to determine the accuracy and completeness of the information provided to the CRA.