Vodacom bad practise

Vodacom has cancelled my active sim card (without warning) which I have been using for my security system for about 10 yrs. There was about R20 of airtime left on it. Admittedly it was used intermittently over the years as it only sent alarm activation sms's and occasional test reports. But it was active. It was even linked to my active profile on the Vodacom website. In addition my security system has been compromised for a time of which I was not aware , which could have exposed me to danger and loss of goods. They have now allocated my sim card number to another client. It is futile to contact Vodacom as all one gets is an automated response and a computer Bot who cannot deal with out of the ordinary problems. This is a frustrating practise of large corporations like Vodacom these days. There is no provision by these corporations like Vodacom for any means by their clients to get personal service or to contact someone to assist or to be able to contact a Manager. The Managers and Directors have placed themselves beyond reach of their clients. So now I have no recourse or means of getting a refund of my airtime from Vodacom which they appropriated for themselves or even an explanation as to why they cancelled my sim card. I am intending to lay a charge in the Small Claims Court against Vodacom and subpoena their MD appear before it, as a matter of principle.