Sorry, but I cannot guarantee that a dream I have will automatically give me the idea for an advertising campaign. In addition, I think that if people create advertising ideas for you, they should be paid for this. The ideas are their intellectual property, whether they arise from dreaming, brainstorming or any other method of idea generation. People in the advertising and marketing industries get paid for their work. To be honest, your "creative task" sounds like an assignment for a marketing course.