cash back claim

oldmutual is full of **** I've claim a cash back last month 25 September I was told it was paid in my bank account I told them I never received it that's when they say oh it was paid on my old mutual bank account which was blocked long time ago and it bounce back they said I must gave them my banking details and I did on the 13 October 2021 I went to the branch to query that I still didn't receive my cash back they told me it was paid on the 30 of September 2021 in my bank account and I didn't receive it I went to print a statement even to day I didn't get the cash back,,,now I wanna Cansel all my policy with them cause it shows when I'm gone my beneficiaries won't get paid I was with old mutual since 2014....