Just report to SKMM. Last year i've been overcharged with my DG billing (postpaid line) which require me to pay all charges before they deduct the following month. Me then call SKMM which advise me not to pay full amount and lodge report with them. Go back to DG SC tell them i'll only pay what i had used only as per advised from SKMM. (save my hard earned money for that particular month, next month bill next month pay larrrr! )