No Service from HOC department

I am an insurance broker for our mutual client, Mr MJ Gildenhuys, Policy number: HLB***. Since 12/11/2020 we have been attempting to cancel the HOC with Standard Bank as the insured wishes to move the building cover to his personal policy with Santam. We have emailed ***, *** and *** with NO REPSONSE! The client is threatening to go the Ombuds. Please allocate this request to a consultant as a matter of urgency.