Airtime

I have R5,45 airtime which was R7.00 last week, don't know what happened to my R2 but when I try to make a call it says I have insufficient funds to make a call. Even when I have R2 in my account, I cant use it. My price plan is that pay per second. How much do you charge per second? R10? then I try to call your call centre, non of the options transfer me to an consultant!!! what's wrong with you MTN? This I day light *******!!! Please contact me urgently otherwise I'm moving to Vodacom!