No authority to debit my account FIX IT AND PAY

Netstar has debited my account without my consent. I have indicated to Netstar to debit the correct account, now I have a returned debited in my bank account. I did not give them the authority to deduct from my salary account. Account is only linked to my First for Woman account. Netstar to write a letter to my bank to request a removal of Rd from my account. Nestar to may R 150 unpaid fee from the bank. Netstar to use the account the I as a customer has given to them to deduct. all their calls are recorded confirming bank details, it's the very account I used to do a debit check. Netstar has been debiting from 1 account, what has changed???? who gave you authority to deduct from my salary account? This is not allowed according to the CPA.