There are few reasons why this can happen. First, please ensure you have given Google Analytics enough time to update. We recommend a clear 24 hours after our traffic has finished.
The 2nd thing to look at, is the speed and size of your campaign page. Does the Google Analytics code get triggered within the 5 seconds before our Skip Ad button is shown? If not - people will be skipping your advert before GA counts them.
Another thing to check is how fast your page is loading, especially under demand if you have ordered a large campaign and are receiving a lot of visitors. It might be fine when the campaign is paused but resume the campaign and you might see your webpage speed decline rapidly. Again, if your website is displaying or loading very slowly, the 'Skip Ad' button will appear before the GA code is triggered.
Another thing to check is the location of your GA code, it should be located just before the closing </head> tag on your page. If it is in the <body> for example - this will delay the trigger of the code by potentially a long time (depending on the size of your page and what else it is loading).
If this does not help you to solve the problem, please contact us.