Closed MTN account still open under credit bureauss

We are now in 2025, still battling with this issue my account is suppose to closed but shows open under the credit bureau. MTN has caused so much damage with regards to bank applications, and I feel the only option is to take them to court. Why is it so difficult to inform credit bureaus, and by the way I never received my attached ITC cancellation letter in my inbox. I was a loyal client to the bone for years and It's a shame to see MTN becoming anticonsumer