Vodacom contract to prepaid

As n small business owner im on a vodacom contract. As i was away out of state for 2 months on my return vodacom contract were to expire on 31 August 2019 after a 2 year period. If received a sms state informing me that the contract is now in process of moving over to prepaid and that the sim card should be rica i the did it yesterday the 30 Augustus 2019 and was told to go back today because of some thing not working and it might be 24h to take action. Thus morning i went back to voda shop and rica was done successfully. .now al my airtime that was un used is lost R279.80 to be correct . I phoned vodacom complaints and was told that this is not refunded as all vodacom users at end of contracts does get this happen to . I call it *****ing money . No other way is it not