Unauthorised Bank Account Deduction

Two amounts were deducted from my bank account by Avis on 2 separate dates. I have never made use of Avis for any reason. I contacted them on 1 April regarding these charges and I was told that they would look into the matter and get back to me. To date I have not received any feedback despite sending them emails asking them for feedback. I have been advised that I should open a case of ***** against Avis which I will now pursue if I do not have a full refund of the deductions as well as the bank charges incurred within 24 hours (19:30 12 May 2015)