Contract double invoiced charge nightmare!!

Received a 4x bills stating Zero for my 4 contracts. Im not sure whats going on with migration to your new system, but when i phoned i was told my outstanding balance is exactly double (R1482) i pay R742 every single month and i have never missed a payment in almost 10 years with you. Please reverse the double charges and send me a updated bill via email for the R742 as my usual bill is paid monthly. I called to change my debit order date to the 5th and that was done easily. But this double charge does not make me happy. I will not pay double. Please urgently correct this bill and send me a new one via email.