Never had a contract but i was billed!!!

i went into a branch to enquire about a data line, they didnt have what i wanted so i never took the contract up. i then received a bill for the device, which i never had. turns out the consultant took up the contract without me knowing. they said at the time that it was a mistake and that everything will be reversed. i kept getting debit orders going off my account, there was no money for the debit orders as i didnt have a contract and my bank charged me R115 everytime it went unpaid. i want my R460 back for the 4 times you tried to take money that didnt belong to you in the first place! i have been struggling with this since March 2015!!! Please refund my money ***