You might not be receiving traffic for any of the following reasons:
You ran out of funds: Campaigns stop receiving traffic when the account balance has been depleted.
Your bid is too low: There might be campaigns which have outbid you. Contact your account manager or support representative for insights into the bidding system.
Your campaign has been flagged: Make sure to check your ads for compliance flags, which may be preventing you from getting traffic due to compliance limitations. You can check the flags per each banner/URL when you click on the blue flag next to your banner/URL in the Ads tab)
No available traffic for the selected targeting: Please check how many impressions are available for the selected targeting with your account manager or contact firstname.lastname@example.org