It's not common on other networks or on Facebook. This is likely an isolated incident. I've been advertising on Facebook for months and >80% of the clicks show

It's not common on other networks or on Facebook. This is likely an isolated incident. I've been advertising on Facebook for months and >80% of the clicks show up in my own stats, not <20%. If advertisers were regularly being billed for 5x the ad clicks they actually received, this wouldn't just be coming out now.