If you’re running an asset-based campaign (Responsive Display Ads) in particular, it’s important to ensure you have a diverse set of creatives across ad formats. Campaigns with a limited set of ads or assets may have more difficulty serving since they are eligible to enter into fewer auctions and have more limited reach.
What you can do
Check your campaign’s Ad Strength to identify if creative coverage or quality can be improved.
Need something else?
Check other common reasons why your campaign performance is fluctuating.