Slow attitude in refunding wrongfull deducted fund

I cancelled my Discovery insure policy on the 12th of May after negotiating better rates for insurance. Unfortunately to find that the call centre agent never actioned the request and I have now been double charged by two separate insurance companies. What really annoys me is that Discovery now wants me to wait 3 to 5 days for a refund after they wrongfully deducted an amount of over R1100 off my account without taking into consideration that I have other financial commitments for the month. I have email proof of the cancellation notification received from them and have already removed the tracking device from my car yet Discovery has no urgency in refunding me my money!! This is unacceptable!! I have to constantly phone after them and no one calls back as they promised. I'm very disappointed in their service and how they treat customers that cancel. I will seriously reconsider using them again! This has placed me in a very unfortunate position financially - POOR SERVICE DELIVERY!!!!