Information on credit ratings is kept by the Credit Reference Agencies (CRA) who are under a legal obligation to publish accurate and up-to-date information. If any information is disputed, the individual concerned should write to the relevant CRA. The CRA will then flag the entry in question as a disputed item which should not be relied upon, while raising the matter with the relevant lender in order to reach a view about the validity of the entry.
An individual in dispute about an entry on their credit file can also ask the Information Commissioner to consider the details of their case.