poor after sales service

I app**** for ADT in Jan 2016 I was told by the sales consultant that I will only pay my first debit order in March as I get 2 months free service. Martin, the consultant that assisted me said he will mail me all the contact details I need. Which I never received. I filled in the forms and put the debit date the 20th of each month. To my surprise on the 9th Feb the debit order went through, I first contacted Martin via e-mail twice, he just didn't even bother replying to any of my mails, I then contacted the call centre to get this fixed and to refund me. After 2 weeks I reversed the debit order myself at the bank. AGAIN on the 9th of March the debit order went through. I phoned again, and advised that the payment should only go off the 20th of each month. I insisted that someone fix this and contact me back once done. Still no one phoned back and I had to return the Debit order myself. I now receive an e-mail stating that I'm in arrears, with R388.50. This amount should go off the 20th March so why am I in arrears. Im not even with ADT for two months and Im already so sorry I joined you guys. I want to cancel my contract as you guys have already breached contract from your side.