A line item in Google Ad Manager can go undelivered because of several reasons and you need to troubleshoot line item delivery to get to the issue. According to Google, here are the most common causes:
As you know, Google can use dynamic allocation to let any line item to deliver as long as it pays the highest and the guaranteed campaign delivery is in pace. So, your Ad Exchange/AdSense line item can sometimes lose to Ad Manager line items that result in non-deliver of AdX line items. And, you can imagine exactly the opposite situation where Ad Exchange line item delivered over the Ad Manager line item as it bid higher for the impression.
In these cases, you don’t have to do anything as the behavior is expected.
Roadblocks are usually the reason behind non-delivery problems. Your page may call two line items in an unintended order, selecting the low-priority line item first. Now, because of the roadblocking, the line items wouldn’t deliver.
You’ve to change the order of request or use GPT’s single-request architecture callout.
Discrepancy b/w line item and pricing rule CPM:
You might have inadvertently set line item CPM lower than the UPR (pricing rule) CPM, preventing the delivery of the line item.
Other than the aforementioned ones, bid timeout, losing to higher priority line items, and creative issues are some of the common causes. Need help with the troubleshooting, get in touch with us.