Im not happy with the service

good day,

i have an account that has 2 decoder linked, my monthly payment is by debit-order, last month my debit order was 302, i went into the app and saw i was owing 702 for the month of may, how is that possible when i pay via debit order then they come back and say i owe DSTV 200 of which is not my fault i was told that if i dont pay the amount i will be disconnected , when im clearly not at fault, the system failed to calculate why am i paying for DSTV mistake, please rectify the Mistake ***4