Unhappy client

When I bought my property, I was given a home insurance with Absa... I immediately told them that I had taken building cover with another company and wanted to cancel this insurance as it was never even underwritten with me. I was then asked to send supporting documents that confirmed that I had another insurance for the same property.. I sent the documents and while they were vetting my current insurance they were taking premiums from my account and my current insurance was also taking insurance which made me dual insured. They finally cancelled thr policy but getting a document confirming that they have cancelled the insurance proved to be another headache because I had to call the company for about 3 times asking them for the same thing. And finally I get an email that said that the Absa policy had been cancelled but this email is not on a letterhead,there my details on it. It just gives me the inception date and cancelled date. How am I supposed to send this email to my current insurer that is insufficient of all the information? How am I supposed to say to my insurer that I was dual insured if it doesn't even say that the previous insurer was Absa... I found the email sent by the adviser very unprofessional.