MerchDesign AI is finetuned to generate Coloring Pages, Sticker designs, t-shirt designs and notbook covers. Using prompts from other AI platforms as is such as MidJourney will not yield the results you expect.

For best results, simply describe your subject, do not describe a coloring book page or add sizing info like this example. The example on the right attempts to use a typical prompt from other platforms, the one on the left is a simpler prompt and allows MerchDesign AI to work it's magic and generate a better image.