Unhappy client

I got a call from *** with great offer to reduce my subscription with same benifits, Security questions asked in the beginning, but then at the end want bank account and ID number. As much as I explain due to ***** activities I get asked over and over to provide my ID number after discussing all the contracts. If Vodacom, very upset with with their service! called the normal 082 client care number, but no response, just busy all the time. Been a loyal customer for many years, Why validate my details if you have them for years!???