Unauthorised debit orders

This day the 25.08.2015 I checked my balance on my account only to find there is an unauthorised debit order from some GREYSTONE... that I don't even know,i googled it only to find that this company deals with electricity outages so I have to pay every month for what I don't know because firstly I stay at home with my mother and she pays all that electricity water !!!!!! so what does this have to do with me and how did they get hold of my account details.somebody HELP !!!please SKELEMS <br>