Cancellation NOT correct as per signed letter

On 01 March 2016 I forwarded a signed letter to Own Your Life Dept. advising them them that I am resigning from the programme< i further advised them that my Gym contract is ending 31 March 2016, to my shock, today, 22 March 2016 I received an sms and an email confirming that my termination date is 30 April 2016, I have the letter as proof confirming that I advised them that termination date is 31 March. They have responded to me that the letter was received and that there will no longer be any debits as of 1 April 2016, however, these emails and sms received confirms otherwise, as it means on 1 April 2016 Liberty is still going to deduct monies from my account. I will do everything in my ability, including involving the Media should Liberty Own Your Life deduct premiums in April as I have followed the correct process by giving them NOT 30 days, but 31days notice of cancellation. Secondly I have a letter confirming that OYL will refund 15% (R276+) for \loyalty thank you\", this is not a concern if I get it or not. My concern is cancellation of the policy"