CSP not really design to make Pixelart, (most will recommend Asperite for pixelart) when you resize at CSP (or any software for painting) they will have some smoothing effects and it will create more color for that effects. in software that design for pixelart they wont creating new colour. (since pixelart have limited color palette).
you still can use CSP for Pixelart but you need to be careful not to use any effects that will increase the color and not to resize it at all.
you can always draw new Art, and if it count as Pixelart we would gladly accept it
It's a good start for a beginner, but PJ is quite strict with colors, the colors in this piece alone are 124, with too many of it are too similar, there also some "artifact" in this piece, it seems you maybe at one point accidentally save it as JPG format , or improper resizing .
Sadly we cant accept this submissions at this conditions, you can edit it and try to reduce the colors to maybe 20 ish colors and re-upload it and we will gladly accept it.
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