Experian refuse to remove prescribed accounts

How does one go about to take legal action against Experian? I've been complaining about accounts which have subscribed but they keep asking for proof of when I last made a payment even though all the information is available on my credit report. They re-instate old accounts from up to 6 years back on my account to ensure they drop my credit score. Capitec sold my account to DMC in 2021 and yet Experian keep both accounts on my credit report even though the Capitec account has prescribed. I haven't been in communication with DMC and never paid them any money because I never had a contract with them but Experian seem to enjoy making people's lives hell and it's evident by the amount of complaints listed on HelloPeter.