Change of Insurer on Property Bonded with Standard Bank

I decided to change insurers on my property which is bonded with Standard Bank, I called their home loans contact number and was told to submit my change in writing, to their home loans client services department at email address: ********** , to log the change. I submitted this on the 15 August 2017, I received no response to indicate if my email was received or is being processed. I emailed this number again on the 17 August 2017 asking for an update and still no response. I cannot find any contact number or even the email address I was given on Standard Banks website, I need confirmation so I can cancel the old policy before the end of the month.