TELKOM TAKING ADVANTAGE OF OUR BANK ACCOUNTS

So I opened a contract with Telkom, only because I already had a contract with the. We agreed on a certain amount which they deducted with no struggle. As usual, crazy charges just appear with Telkom. They gave me unlimited airtime, I asked a call center agent from telkom about the airtime that doesn't finish and doesn't appear on my balance, I asked her to check and told her that they better not charge me for things I don't know or didn't sign up for. Than exactly as I predicted out of no where my amount doubled. I went there and asked them why did they withdraw so much money from my account? The consultant said they gave me more airtime, that I didn't sign for.