My wife took S/S in 2017 at age 62. As a corporate executive, she retired/cashed out $400K which caused her Social Security benefits of $25,200 to be taxed @85%. We now have received a bill from the SSA requesting a payback of $25,278. Can we request an amendment to our 2017 or 2018 tax return as we paid over $7K (35% tax bracket) on the monies received that the SSA is asking for it back??