I'm cancelling my policy regards to poor service

I took an investment policy with liberty in Durban CBD liberty towers and a girl by the name of Nokuthula was helping with regards with filling up all the forms now the problem is they deducted money on the 25th while I told them specifically to deduct money on the 27th every month, now the took away money in my account that I saved to go to work, cos I get paid on the 26th, who gave them any right to take away money on the date that is not on the agreement form? I need the manager to call me and explain to me why they did that and why when I speak to Nokuthula as an agent she says that's not her problem I can cancel the policy if I want to than block me on Whatsapp, what kind of an agent is that? I'm so angry and I need the manager to call me and explain to me whats going on or I'm cancelling the policy and I wont recommend no one again to use this policy!