Donate the proceeds

This refers to your front page apology published on January 18th. In my opinion, you may prepare a list of blacklisted persons and organisations for prior verification before accepting advertisements from them.
However, I believe you should not forgo the amount due for the advertisement. You should rather take full payment and donate the amount to any charitable organisation of your choice. You may add some more as a gesture of 'penalty' for accepting the advertisement in error.