I was taken out of my job in 2018,no hearing nothing, after months went to Labour department foe my UIF, and I was told that Claudia Ceresa said I resigned as I was reaching my 60's,she cannot produce my resignation letter

I was taken out of my job in 2018,no hearing nothing, after months went to Labour department foe my UIF, and I was told that Claudia Ceresa said I resigned as I was reaching my 60's,she cannot produce my resignation letter. I mean there is a lady who is over 75 she is still working there. Why did this lady tell lies, when I loved my job and people I was serving they still have a problem