Cancellation

I sent an email trying to cancel my policy with Old mutual and I am not getting any response what so ever. The debit order went off for the first time this month and the debited amount was not what I had agreed on ,furthermore the emails received on the cover I took is uncomprehensive and shows the cover information in bits and pieces. This kind of service is unacceptable and it just goes to show how I will struggle if I ever need to claim.