Does MetLife have the right to seek repayment 20 years later?

I was working for the school board of broward county fl for more then 20 years. I came disable for there and Metlife was paid my check but sudenly one of the representative or my case manager was tell me about allsup company to help with the social security aproved but really they didn’t nothing. I did what I have to do, send papers to social security and finally they aproved me but the social security didn’t say nothing to me about so I check my bank and suddenly I saw money on my account 16.000 thousand and Metlife write me then I have to paid then that was overpayment but what overpayment they stop my check before and social security didn’t let me know. Then I was aproved, now I paid to Metlife 4.000 thousand for no reason. I want Metlife to return that money back to me. How can I resolve this? Thanks.