Unauthorised debit order and rude service

I signed up with the box fashion and we agreed on a debit order date. However they decided to debit my account on a different earlier date. I tried to contact them and firstly struggled to have my call answered and when it was finally answered the lady was rude and *********** and kept saying that she cant find my details on their system. I was made to wait for a whole week to receive a call from their accounts department and they refused to correct the incorrect debit order. This is nonsense and I am afraid that they are gonna keep debiting my account at their discretion.