Help with Reason rejected

It's very nice, but pixelated. As you created that in Adobe Fresco, I wonder what the initial size was. You should start with a much higher resolution and use, whenever possible, vectors for lines.

And you should avoid errors like this:

1. “Frame” because the background does not cover the whole picture
2. Cut-off (hard) geometry instead of “natural” (soft) borders. This looks like, at some point, you expanded your art board. That is, however, visible in several instances, so I doubt that this was the case.