Case ***6 at Telkom for suspension due to incompetency from Telkom not resolved

I have never in my life experienced such a horrible experience, On Tuesday 15th October I logged a complained with Telkom after they suspended my account due to "non payment". Which the non payment is a fault on their side, I took a device (iPhone 12) with Telkom in October, i then returned the phone due to the fact that i didn't want a new contract i wanted to upgrade, of which i did, The courier guy fetched the iphone 12, returned it and brought the iphone 13 , However telkom did not remove the iphone 12 contract from their system and now they claim i owe them for the device which i returned and confirm with sell direct , they game me a ref number IC*** to confirm that the device was returned and received. I spoke to Chahida from selldirect who confirmed the email was sent to OBCc, i have spoken to several agents from telkom trying to get response with my query, I have spoke to Thabile Masuku, Lerato Lephondo Yonela,Monewa and Denisile, I requested to speak to 2 mangers Jabulile Malete and Lizeka Ntabeni whom did not even bother to return my calls was told that my query would be resolved within 72, its been 6 days since my case ***6 was logged, I'm upset and frustrated and I need this query resolved today. Telkom has by far the worst service I've experienced. They are *********** , and unhelpful