Hello friends,

I got my Green card through self petition 3 years ago while working full time for a company. I had provided them details about my status change then and now after 3 years, they tell me that my FICA taxes were never taken off and I have to pay the unpaid FICA taxes of the last three years which comes down to 25k+. What happens if I don't pay those taxes, will there be an penalty or interest over time?

Thanks.