Old Mutual's Gross Incompetence.

I have been struggling since March 2019 to get the banking details changed on my husband's annuity payment to my bank account. He has become disabled and cannot conduct business for himself. As I am the beneficiary of this payment when he passes away, I did not think that this process would be so difficult. I also have power of attorney for him. As the months have passed, every time I asked them why the process has not been completed, they have given me another form to complete. One would think, for a company as big as theirs, that there would be a standardised pack of forms to be filled in. But no, there isn't. In October they sent me a form, supposed to be THE VERY LAST ONE, which I had to fill in. The usual person I dealt with wasn't there that day, and I have just found out that the person I gave the form to, lost it. It is now the 10th month since I started this process and it is still not complete. I find out now, that the person I usually deal with has gone on leave, and their service department is just pathetic. My husband is seriously ill, and if he passes away before they complete this process, and his present bank account is frozen, I will literally have nothing to live on. Is there anyone who can help me sort this out?