The Irony of the Day

So this morning, i was leaving the house, and i took a letter that was delivered to us by mistake. We constantly get mail for Lemarchant st. I'm not sure why, but in any event, it happens probably a couple times a month. Sometimes i leave it in the mailbox with a note for the Postie that it was the wrong address, sometimes i just drop it back in the red mailbox. So this morning, i take the letter, with the intention of putting it back in the red mailbox. Lo and Behold, right next door is the mailman. So i approach him, say goodmorning and give him the letter and explain the situation. He takes it, promises me that he'll deliver it today and apologizes to me. I told him not to worry about it. So then he starts telling me, mistakes happen, I'm sorry... etc. Again, i tell him not to worry about it, but he is all flustered. I'm not really concerned, or angry, i just wanted the mail to get to the right person. So i bid him a good day and continue on my travels. Anyhoo, i come home today, and what do i see, but in our mailbox, another letter for the people on Lemarchant (a different one than the one i gave him this morning)! So now, i think this is funny. It's happened several times in the past week... so do leave a note on the letter again, drop it in the red box, or is this a matter that Canada Post needs to be aware of?