My employer reduced the tax withheld in W-2c after I repaid the gross of overpaymant

[g-satish4u]

My employer asked me to repay gross overpaymant of $2500 ($2000 net + $500 taxes withheld   for november 2016)  in march 2017,   I repaid it and got W-2C. in W-2C my employer reduced the tax withheld  also along with wages. Is it correct? How can I get tax withheld amount back for that overpayment

[JaimeG]

If your Gross Income from the Original W2 changed, so should the FICA (Social Security and Medicare). Basically it does not sound correct because your W-2C should reflect a change at least in Boxes 1-6. When you reimbursed your employer previously paid wages, your entire numbers changed because each number in Boxes 2,4 & 6, are a percentage of boxes 1,3 & 5. So your entire W-2C should have changed due to this reimbursement.