Anyone who's been reading this board for very long will have figured out there are good responses for the points raised by your antis. It sounds though like you expected them to instantly change their mind without countering your point, you had no further arguments prepared. It doesn't work that way, you need to take their responses to you and give them specific reasons and new information to consider. You'll have to do this many times in a calm rational manner if you can hope to make a dent in the problem.