Rejected as "Intellectual Property Refusal"

Hey. Two drawings were not accepted for me due to "Refusal of intellectual property", I cannot understand where the intellectual property is, these are my drawings and I have a sketch drawn on paper by me. There is no mention of brands in the title and keywords either. Someone can explain to me what is wrong with this picture.

name

merry christmas and happy new year greeting card with cute retro car with christmas tree on the roof, postcard, poster, vector illustration, flat design

keywords

auto, background, banner, car, card, cartoon, celebration, christmas, cute, december, decoration, design, doodle, drive, fun, gift, green, greeting, hand, happy, holiday, illustration, isolated, lettering, merry, new, pine, pink, postcard, poster, print, retro, scandinavian, snow, style, tree, trendy, vector, vintage, white, winter, xmas, year