Standard bank funeral policy

Standard bank did not pay my claim after the death of my mother,i cancelled all the policies that i had because they promised me that they are going to cover my mother with the amount that the previous company covered her with,i must send them the proof of cancellation in order for them to cover her, and i did that on the 13th of December and i recieved the acknowledgement of receipt from them on my email,unfortunately my mother passed away on the 18th december...standard bank declined my claim and they didn't even call me letting me know about that,i called them and they denied that i sent the proof of cancellation to them,i had to foward it again to them but still they didn't get back to me. I called them again,they say i must send the email to compaint department at standardbank and i did that it was on the 11th of January 2021. I have not received anything from them even today(no call,no email,no money) but they are still debiting for my mother's policy.