I completed my 2017 1040 using Turbo Tax and everything flowed correctly to the 1040 including my withholding and tax calculation. Turbo Tax completed form 8959 correctly and the total additional Medicare tax flowed correctly to line 62 of my 1040. When I received my tax refund, my refund was reduced by the exact amount of the additional medicare tax. A later IRS notice indicated that my refund had been adjusted but gave no explanation. Any help or thoughts would be appreciated.