If you need to get in touch with a creditor, you may be able to find their contact information in your credit report. Sometimes what may be available is only the name of the creditor.
If it’s available, it’ll be in the Accounts section of your reports.
Click to expand the account in question to see details about it. The creditor’s contact details would be found in the Contact Info section.
More information on how long collections accounts remain on your credit report is available here.