Bad service from vodacom

I recently took a contract with Vodacom at the workshop. IPhone 8Plus deal with a very helpful young lady by the name of ifhana. She was very helpful and kept me on the loop. We did everything quickly and I rececived my phone and paid for the sim activation and sim card etc. This was on the 27th July 2018. She advised a Further R162 would be deducted with 48hours for prorata services and I agreed. I called her 6 days later and spoke to her and she advised on the phone that she can see the 162 went off and was paid because I advised her i have received 3 invoices and I want to know which one would be deducted on My salary date in August and sent me the summarized one and advised I should ignore the other 2. All was good and well, the next day (7th day) all of a sudden Vodacom tries to deduct R162 from my account. No notification goes through my phone the debit order is returned because of insufficient funds my bank charges me R150 for a returned debit order. Yesterday I check my statement and realize my account is overdrawn by an amount and it shouldnt be. I find out that Vodacom only debitted my account 7days later and I had provisioned and reserved funds for it to debit on the initail 48hours because I have previously had unauthorised debit orders going off my account. I would understand if they notified me that they would delay so that I could ensure there were funds on the day they wanted to debit but now I want them to refund me the charge of R150 by the bank. I dont mind paying the R162 because it is part of the deal we have, but the delay was on Vodacoms side therefore they need to call me, reschedule the debit and refund me the R150 charge from my bank. Ifhana at Vodacom workshop is aware of the situation. I have just taken my contract with vodacom and I already have a problem, please kindly rectify this situation as it affects my credit score.