DearSir.
Iamwritingthislettertoapologizetoyouforthemistakethatwesenttheshoesinwrongcolor.Ihaveacknowledgedthatmyfaulthasbroughtyougreattroubleandunconviniences.Iherebyexpressmydeepsorrowforthismatterandwearegoingtodoourbesttomakeituptoyou.Iassureyouthatthismistakewillnothappenonceagainandwouldappreciateverymuchifyoucouldgiveusachancetoshowoursincerityonthismatter.
Bestregards