Vodacom Sim caller ID

I have a top-up contact with Vodacom for the past 5 years. Few months ago my son, who is using the sim, complained that all incoming calls appear as unknown numbers. I called #082135 today and was told that for an extra charge the caller identity can be activated on the sim. I am not happy. This service was deactivated on my sim and why should I pay to have it reactivated again. Any sim card should at least show the number calling. Even numbers saved on the phone does not show a number or name. This is unacceptable and I will not pay a cent more, in fact I will rather leave Vodacom and take all my contracts with me. I was promised that a Supervisor will call me tomorrow, on Good Friday, at 08:00. This I will wait to see.