Dishonesty by Old Mutual for death claim on Annuity

My late husband passed away in 2018. I was the only beneficiary on the annuity. But to date Old Mutual is not honoring their agreement with the deceased. They are telling me me that they need to pay the money to a person not mentioned on the beneficiary form. So please don't do business with this company they are dishonest and I personally will never ever have a policy from them or even one that is underwriten by them.