********** debit

So i received an SMS saying "Your MBS247 R126.69 debit will run 15 Dec 2017 sold by Straton ********** 093 ref STRATONVH0STR ********** ********** 15.Respond for hep" what the hell, i dont even know who this company is or what product they are selling, where on earth they got my number or bank details, i phoned them and they are telling me to reply to the sms, so now i must use my airtime to respond to this sms which i did not sign up for, this is ridiculous. Dear Straton, whoever you are do not dare debit my account or consequences will follow with regards to ur ********** ways.