Wrongfully canceling home insurance

I bought a house, financed by Standard Bank, and took home insurance with them. Few days after registration Standard Bank cancelled my cover and when I check with them they say it was cancelled because I told them I have insurance already from other insurance companies. I told them I never did that and I don't have insurance with other companies. They asked me to leave my contact details so they can get one other consultants to contact me and discuss this matter. I have left my contacts twice but I'm still waiting for their call and it's been two weeks already and my property is not covered