Bad experience

Unfortunately I cannot complinent these two banks. Years ago we bought a property, a life insurance was taken out as requested by Fnb. (That time from NBS). I got divorced and my x got the house. I did not know that our life insurance was claimed by my x, it was a joint bond and joint life insurance. As far as my knowledge goes, if there is any changes on the home or joint life insurance for a claim, both parties have to sign. In my case the banks decided they do not need my signature and paid out my life insurance to my x so that he can pay off his bond. I hava laid complaints with both banks, Nedbank says that Fnb did the claim, therefore they did not need my permission, Fnb said that the owner of the house did the claim, not them, they have only advised him that he could claim our life insurance. It has been handled unprofessionally. The problem is still not solved since 7th of July 2021. I only find out about the policy claim in July 2021, thank you to someone I knew that send me the letter from Nedbank regarding a short payment they did. I have claimed the "short payment" and now all of the sudden Nedbank require the other parties signature. I do not understand how they work.