The very first thing you want to do is read and understand the FCRA. This act is what protects consumers from from false, erroneous, and outdated reporting. It will help you understand how to and what to dispute. Read the HIPPA as this will pertain to medical debt and collections. Read the FDCPA as this will pertain to collection accounts. You must have a thorough understanding of all of them if you truly want to enter into and be successful in your credit repair journey!
Was the account closed by you or the creditor? What type of account was it? How old are the late payments? Was the account closed in a positive status? These questions will better the responses you receive.