Credit balance from Telkom

I have a credit balance on my Telkom account after they advise me to cancel the existing contract and to reapply for a new data contract, which was a stupid idea from the sales lady but besides the point. I can't phone them on my mobile phone as they can take up to 2 hours before answering a call. I would like them to make contact with me or send an email address in order for me to receive my credit balance