I came to USA in 2001 as F-1, then worked on EAD, then changed to H-4, then went to Canada for 3 years. Recently I came back to USA to work because my wife ted I-485 and got me another EAD.
I am still using the SSN I got when I first came to USA on F-1.
The HR told me that I do not need to pay Social Security Tax and Medicare Tax. Is that true? I do not want to get into trouble if I have to pay Social Security Tax.
Another question, if I pay Social Security Tax now and leave USA later, is it possible to get it back after I become 60? I heard in theory it's possible but in practice impossible.
Thanks!