Just got a letter from IRS, I owe anther $3000, they adjusted my income , what did I do wrong ?

We have no idea.  What income did they change?  They must be saying you left off some income.  Or put down the wrong taxable amount on a 1099R.  Or reported something on the wrong line.  Did you get any 1099Misc and not report it on Schedule C?

in 2 to 3 weeks you will get a notice from the IRS as to what they changed.    you can call 800-829-1040

select language then #2 then follow prompts.  be prepared to be put on hold for a while.