No answer in the billing department

I have endeavoured to get through to the billing department for two days now, holding on in excess of 1 hour each time I phone in order to query a balance brought forward on my account and a credit that I should be receiving but I cannot get to speak to anyone on the phone on *** - supposedly the billing line. Seeing that I cannot get hold of anyone can someone from MTN billing contact me, I cannot afford the time that you want people to hold on the phone in order to deal with a query