Two things stand out to me. That would make me pass your post.
1. Your icon is blank. That leads to people passing you for someone else. Take a photo of your card room or a shelf showing cards. Something like that. Your name means nothing, people need a face (a photo, an image of something) If I tell you to think of McDonald's what do you see? If I say Nike what do you see? Now you get why the black icon hurts you.
2. is a big one! Your one negative feedback states you are not posting photos of the cards you are selling and are using stock photos. These two things scream con man. These two things would make me pass your post for someone else and I probably have. No one wants to buy a 2ed hand card without seeing it. I also do not buy a card if there is not a photo of both sides.
Do not go over the top with a photo and try and make it look like a professional photo (like you have now.) If you go too far it looks like a stock photo. Put it on a stand or lay it on a table make sure you leave some of the backgrounds in the photo. That little touch will key people into knowing, that is the card they will receive. That makes the sale. 3 photos are the best. front, back, and a close-up. But the close-up is not a make-or-break thing when the zoom is on.
No one that buys 2ed hand cards will buy from someone using stock photos and that one native feedback with the photos you have is a killer. Making these two changes will show people, you are just a regular guy selling cards and that is something everyone can trust. Right now you're not showing that at all. You have zero of the personal touch.
Remember selling things is 80% psychological & 20% of people wanting it. Right now you are only working that 20% and people are one click away from others working that miss 80% you don't have.
What is that behind you!?! Oh, It's me! Looking at the cards you have, That I want. :)