After you file

I am also going through this same thing. The employer I worked for stated I worked for them in 2015. I quit 2014 in December. They made my W2 for 2015 the EXACT same as 2014: 13,656. So now I’m having to pay all the taxes and interest and penalties due to this. I was not working for them as I was pregnant with my daughter at this time and in and out of the hospital.  They now have sold said business and idk where to start. What can I do?