Deduction date changed and I only got informed via sms

I spoke to a consultant by the name Vusimoze from 1life and the call went great I was,happy in recieving the new agreement we had discussed that it will commence from on the month of March ,and told him that deduction can be made every month end of each month. On the 20th of February(yesterday),money got deducted from my account,I was surprised as I thought this would start from month end of March ,to add insult to injury I get an sms being told that they decided to change my deduction date to the 20th ,I was not part of that we why am I being told by sms?why was I not phoned and asked if I would be okay with this arrangement before hand?instead I'm being told to call to enquire,why am I calling about something I never agreed to with people deciding to change dates expecting me to call about something they were firstly MEant to tell me about!!!!!I'm very angry disputed that debit order with my bank because I never went into agreement on that deduction date and I want to cancel the 1life premium immediately,if this is how they truly do things,if I should get a call all I want know next is how to go about cancelling the premium ,nothing else. Tebogo Skosana