Before saving a dynamic condition is very important to check the number of line items that will be affected. What this number means is that the specific amount of products will fall under the condition you are about to create and display the associated ad layout you'll design.
You can check how many line items are affected by the condition at the bottom of the screen, just as shown in the image below:
Once you save a condition, you can proceed by creating the ad layout associated with the condition.
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