Issue not resolved since July 2023 - I am losing business since then

Good afternoon, I am at my wit's end and unsure of how to proceed. Despite numerous calls to MTN and Vodacom, visits to their stores, and emails, and I even drove to the Vodacom shop in Mall of the North, Polokwane, and spoke with the manager. Unfortunately, she was also unable to resolve my issue. In 2019, I successfully ported my cell phone number from Vodacom to MTN with Vodacom’s approval. However, in April 2023, Vodacom issued a contract to a new client with the same number as mine. Consequently, when my clients call from a Vodacom network, they reach the other individual, but calls from other networks still connect to me. I have lost and continue to lose significant business and am extremely frustrated because Vodacom has not addressed my inquiry and do not care. Vodacom made an error and should amend their client's contract, as this number has belonged to me for 20 years. Please assist me and possibly refer me to someone who can rectify this issue. I am at a loss as to what to do next. Nobody can put me through to escalations to get a reference nr