Troubleshooting for line items 

You can now use the Troubleshooting tool also for line items. Go to "Troubleshooting" on the side bar, select the campaign and finally the line item you want to troubleshoot. The provided metrics and bid statuses are identical to the ones used for the troubleshooting of deals. 

Documentation: Troubleshoot line items 

Campaign and line item monitoring enhancements

We've introduced an improved way to track campaign performance, giving users access to key metrics at both the campaign and line item levels. This update makes it easier to monitor performance, quickly review budget and unit capping details, sort them without the need for editing, and adjust time periods with predefined or custom options. 

Documentation: Keep track of campaigns / Keep track of line items