Hard reject to my leather texture pack. What's wrong?

I uploaded my leather texture pack, but in less than a day I received a hard reject. What is the problem? The resolution of each picture is 2700х2300 px. I don’t think that the problem is exactly in the resolution, since I found the goods with much less resolution. Maybe the reason is that the pack is divided into two parts, each with the same samples, just with different lights? Please, help.