@golfperfect1 , while absolutely agreeing with @SusanY1 and @Mike9241 , just let me add one more point --- the interest that Canada paid you on the returned amounts are recognizable as income ( for US tax purposes ) in the year in which you received the income not the amended year. Generally any refunds due is lost after a period ( three years past the tax return due year ) , but tax due is always payble/ collectible by IRS and State no matter how late ( even though in practice they follow up to six years mostly , esp. if the amount is small ).
Hope this and the comments by my colleagues help you
pk
