Did you build an ad set, enabled the loop indicator and realized that, when previewing the ads, they are not looping? Most probably, the original ad duration is more than 15 seconds and therefore, no looping is possible.
To know how long your ad is, simply go to the ad editor and have a look at the exit animation of the layer that exists last. If your ad contains multiple slides, make sure you select the last one.
For example, the ad in the image below has a total duration of 8 seconds which means, the ad can loop 2 times resulting in a total duration of 24 second ad playing.
To ensure your ads loop, the original duration of your ads must be 15 seconds or less. If your ads last longer, simply make the modifications that are needed in the design to shorten the ad duration so it doesn’t exceed 15 seconds and save the changes.
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