is really the wrong place to ask . I would be better to start a new post.
However I’m sure it’s the price. At that level no one is going to buy it on a whim. You have cut off 99% of the market which are hobbyist very small indies. It a very low you are going to find someone with that kind of money to spend (bear in mind a game would have lot of characters so they would need a good budget) and also that their game needs that character exactly. It’s a nice model but your audience is so small it’s going to have trouble finding anyone.
Personally I think if you were to slash the price to around the same as other similar characters, then you would make up for loss in the individual sales in volume.
Then it a question of getting it seen. Unfortunately I think the most eye would be on it at the point it was added.