Telkom Mobile Contracts are a ****!!!!!

Had a cellphone contract with Telkom years back. Ignoring the fact that their network was poor, I honored the contact agreement until it expired (24 Months). Went to their Eastgate mall branch to notify them that I wont be renewing. 6 months later, I was approached by MBD legal collections claiming that my account was not cancelled and demanded a payment. I paid MBD. Now, 3 years later another debt collector is demanding payment for the same account. I've sent various emails to <***>, <***> since 2021 without a response. Telkom Mobile Contracts are a ****!!!!!