Old Mutual stop orders and refunds

I cancelled several policies in March but old mutual is still taking money from my salary through stop order. I went to their offices on several occasions with noo success. Only on the last visit did i get a little help because they refunded me for one month. What makes me angry is that i got an sms stating that there is more refund due to me. There is one policy that was cancelled, so how did this happen if i never indicated that i want to cancel? Also there was a new funeral policy which i don't understand because i wouldn't join while in the process of cancelling policies. I want them to refund my hard-earned money from March and stop taking my money. I have several reference numbers.