********** cellphone upgrade with Vodacom

I've been trying to file a complaint regarding a ********** cellphone upgrade that was done at Vodacom in midrand on the 11th of March 2020 while i reside in KZN and have received zero assistance! I've called the customer care line and the ***** department numerous times, emailed my ID as well as samples of my signature to *** and haven't received any response not even a reference number! This is very frustrating as i was nearing the end of my current contact with them and it's also negatively affecting my credit score as I apparently owe R30 000 for a phone I know nothing about!This is clearly an inside job as it doesn't make sense how a cellphone upgrade can be processed without my approval or signatures and being that I reside in KZN it would make no sense for me to upgrade my contract in Midrand.