CELL PHONE CONTRACT ENDED YEARS AGO BUT STILL SHOWS AS ACTIVE ON CREDIT PROFILE!!!

In 2019 I took a cellphone contract with cell C and it was paid up and I requested cancellation per their conditions. Now many years later when I review my credit report the contract is still showing and I do not even know how it affect my score because we do not even have a contract anymore. I have tried emailing and calling but there is little help as expected. They keep forwarding my emails internally and month after month this stain remains. I need this sorted please!!