Over twenty years with AON, but hugely disappointed!

My spouse has been loyal to AON for twenty-two years, and has a short-term personal lines insurance policy. We recently had a problem with our geyser which was not heating. After contacting AON, they confirmed that this would be covered under geyser maintenance. They referred him directly to the underwriters. We thought this was rather slack of them, especially considering that one of the positive attributes any insurance broker should aspire to, is to make the claims process smoother for the client. My spouse had to do all the legwork. The underwriters did pay for this, to their credit. However, a week ago we requested our claims history from AON. To our shock, we saw that there was a huge discrepancy between what the plumber had on their invoice to what AON had submitted, albeit that this had been finalized. The amount in the claims history (loss ratio) was more than double the amount on the plumber's invoice. We hate inaccuracies, and immediately informed AON. This enquiry was made last week, and today is Thursday! We also find AON's customer service levels have deteriorated, because my spouse often gets cut off when on the line to them. He asks for a manager to phone him back, but this never happens. We are not happy. I am afraid, this is not a good reflection on AON. Is this how one treats a client that has been with you for over two long decades? The main contact person who is supposed to be dealing with this is Sechaba Selokoma.