Vodacom

I have been having a problem with my vodacom phone for almost 2 and a half months,

I have a top-up account with vodacom, so when you look at your balance it shows 2 amounts, a monthly airtime amount that you get every month from vodacom and the I have a Recharge amount. The recharge amount you are able to transfer to a different number. I have been queried why I can not transfer an amount ( I do have available amount) the one call center agent told me I must transfer at least 80% off the amount - this is not true. Then I phoned the call center again and till date nobody can give me an answer why I can not transfer, every time I esquire about this they say they send this to the back office and it will take 24 - 48 hours to give me feedback