Vodacom payment

I have been with vodacom for a very long time, I have just paid off my second contract with thm,now on the second contract I settled it prematurely coz of my financial contraints. I ask for a settlement on the 5th of feb they told me that the settlement will only be applicable on the 7th of the month, on the 7th I called again they told me to call again on the 8th. So I dd that on the 8th I settled my contract, in the same month 23th there was a debit for the amount I have been paying every month so I reversed it thinking they made a mistake, now yesterday they debited again with the same amount including penalties for reversal now people WHAT IS A SETTLEMENT IF I AM SITLL GONA PAY AGAIN