Iam misleaded

I was working for liberty life from February 2015. In June 2020 I received a call from my brother informing me the the library group are looking for me, they then phone me and say I have unclaimed benefit which I asked for what but they said I should send the required documents for me to get the benefits. I did that and they paid me about 74000. Two months later I got a job elsewhere and resigned, they paid me 7000 when I asked they told me the 74000 they paid was my pension, the rude mamtuz a lady who was helping me couldn't answer me. I need help in this regard. How can they trace me to get my pansion while still working for them