Mistake -customer complained to board of pharmacy

i made a mistake ( typed and verified half of a tablet on clonazepam 0.5 mg...and it should of been typed as 0.5mg, so as a result pt was taking 0.25 mg of clonazepam ) Pt complained to board of pharmacy ... Now they want me to give them an explanation ... What is the best way to do it?
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Source Type: forums