Airtime ****

I bought a R110 vodacom airtime voucher on the 22nd of January at the Grove Spar in Nelspruit. 10min later I try to recharge it said the voucher had been used. I called vodacom they told me the serial number of the voucher had been loaded the day before, I must go back to where I bought to get a refund. I went back to spar and they took all my receipts and said they would investigate and call me withing 3 days but I've been waiting ever since. Now who is the **** between vodacom nd spar?