Complaint

I have been receiving numerous calls from Vodacom for no particular reason. Today Vodacom phoned my wife as both our cell phone lines are with them on the same contract and said they want to speak to me because there is a problem with the contract. I couldn't take the call over hence I was driving. When I got home and tried to call vodacom back I was sent an sms that vodacom received high volumes of calls from my number and because of this I can no longer call the customer service. The call was then hung up and vodacom sent me sms messages. I never phoned vodacom for any reason from my number the last couple of months and why is it a problem to call the customer service if you are a customer of the company???