A player whose partner has given an incorrect explanation may not correct the error during the auction. The player must call the Director (the intended dummy is a player until play of the hand starts) and inform his opponents that the explanation was incorrect but only at his first legal opportunity which is,
a) for a defender, at the end of the play
b) for declarer (or dummy), after the final pass of the auction..
Although intending to be 'well meaning', players should not attempt to resolve this situation themselves as unauthorised information may be given in the process.