No risk contract

I'm a pensioner and wanted to scale down on unnecessary expenses. I app**** at Vodacom for a sim only data deal without any device. I was refused. I have no accounts except for the normal month to month expenses like utility bill, funeral cover plan and my Telkom account of more or less R500.00 per month. The sim only deal is on offer for R299.00 per month. I wanted to cancel my Telkom account which I have been paying for the last 20 years which would give me a saving of R200.00 We all know if you don’t pay your month to month accounts your telephone or electricity gets cut off. I have given proof with my bank statements that all my accounts are in good order and have been for many many years. What I can't understand is that Vodacom with absolutely no risk on their side refuse a small amount of R299.00 per month. You pay for the data in advance, so if for some unthinkable reason the debit order is not met you just don't get the data. There is no risk and not even a phone or router involved. I was given a Vodafone router from my children who moved to the USA which by the way are paying four Vodacom contracts monthly until the end of the contracts without being able to use any of them. That's a nice freebie for Vodacom.