Disappointed, angry and saddened

I got divorced September 2019 the pention fund of which I was supposed to get 100% from old mutual, only to find out after being there several times within 4months that the money has been paid out in full to my ex husband, who is also and ex employer of Old Mutual. I am so disappointed and stressed out that after me being there several times only to be told in December "sorry for the inconvenience, but the money has been paid out in full to your ex husband in August 2019". Can someone please assist me on how to go about getting back what rightfully belongs to me, I'm a mother of 5, unemployed and the only person I fully depend on is my mother who is a pensioner. I would like to know how it is possible that only after so many months a payout reflects on old mutual system.? Should it not have reflected the same day that the payout was made?