federal tax id number

I had a federal tax id number and now that I got a work permit and a real social security number I was supposed to turn back in the TIN but I've lost it!

What should I do? Can I get in trouble for not returning it?

Thanks
Mauka

I had a federal tax id number and now that I got a work permit and a real social security number I was supposed to turn back in the TIN but I've lost it!

What should I do? Can I get in trouble for not returning it?

Thanks
Mauka

You can get your TIN number from your last Income Tax Return and inform IRS about that and file your new Tax Return under your SSN.
Good luck.