NO CLAIM CASH BACK BONUS

Sometime last month I wrote this kind of a review and was promised a resolution. My issue is the cash back bonus that IWYZE gives back if there was no claim submitted in a period of 3 years. I had an accident on the 9th of September 2015 therefore I made enquiries after receiving communication from them in February 2018, advising about this bonus and giving me a figure as well. I called and send up and down emails finally I was advised that the 2015 claim has been closed therefore I will be entitled to this bonus if there is no claim before the 9th of Sep 2018. I dealt with their complains dept who advised me that they have send my request to their finance dept who will then advise on the amount. The person I dealt with also advised me that payment will be made on the 10th of September 2018. I have not received any feedback, its been more that a week. Last week I called and send emails again to this lady but nothing has been communicated to me. Is this fair? All I want to know is HOW MUCH & WHEN. Other insurers are offering these bonuses on a monthly basis IWYZE does it after a 3 year circle. I am still with them because I am committed to them and have never had issues before, their service is also excellent, so why spoil this great relationship we have?