Excessive insurance charge

I am disgusted how Standard Bank Insurance have been over charging me for years! My house is on the verge of repossession and I am trying to reduce costs where possible. I have been paying structural insurance at a premium of R1900 per month, I asked for a new quotation and suddenly my insurance is R800. Property does not devaluate and I feel like money has been ****** from me. I never really noticed the high premium as it was linked to my bond and now I realize that my insurance has been a large contributing factor to why I could not maintain my bond repayments. I would like a refund