unauthorised or ******* deductions

I believe the bank is being negligent when it comes their security measures on protecting my money or our account I have called several times to query insufficient amount that are being deducted on my acc every single day twice each day to br precise but. nobody seems to know nor understand how that has come to be been send from one consultant to the other at the point my acc is sitting on -400 due to those small amounts going out.i need clarity on how is that possible I only subscribed to iTunes. my contact details ***