Sos Please Help

[lagnaf69]

Ok folks this is all new to us... My husband was born in Canada, his father was born in canada his mother here in Michigan in the United states...
He lived in canada till he was 4 years old when his parents moved to the United States, upon crossing the border, his parents provided alot of information and his birth certificate was stamped with the following

IMM & NATZ> SERVICE DETROIT MI Oct 1 1962
Class 301 (a) (7)
to PERM

no one at the Immg. Office could tell us what that meant, he was always told he was a us Citizen and now hes told hes not but no one can tell us what the stamp means ...he has been here since he was 4 years old and had no knowlege of any problems has a SS# but unfortuntly it was destroyed and when we went to get a replacement they said no!!
What do we have to do to find out what that stamp means??
Please help as this is preventing him from getting a job (he was recently laid off from his job of 28 years here in the US
we are at a total loss and due to unemployment totaly broke & can't afford a attorney
Please help!
Any help will be greatly appreciated
Thanks in advance!