No refund on a prepaid airtime purchase for a old Vodacom number which has now been ported to Telkom

I purchased prepaid airtime from my Capitec account of R100 for a number that used be a Vodacom number which is now a Telkom number. Capitec says they cannot reverse prepaid purchases & that I must contact Vodacom. I can't get to speak to anyone on your phone numbers & your Facebook page says there's nothing they can do. Surely there must be a way for me to be refunded, otherwise this amounts to theft