Your campaign is being reviewed to ensure it is safe, appropriate, and comply with each platform's advertising policies. All content in your ad is reviewed, including your headline, description, keywords, destination and any images and video. During this process, the ad’s status will be "In review".
The advertising platforms review most ads within 1 business day, though some more complex reviews may take longer. Your ads will be approved if they find the ad doesn’t violate any policies, and your campaign status will be turned active and start to run. If the review indicates that your ad violates a policy, your ads can’t show anywhere and you’ll be notified of the policy violation and told what you can do next.