There are currently no statistics for this advertisement

Despite ads being live on my site for over a week, with all of the ads "actively being displayed", all of them are reporting "There are currently no statistics for this advertisement". Yet the should by now be reporting several thousand views each, based on other traffic analysis, and presumably some clicks.

All ads display correctly, and clickthrough correctly. I've explored the issues here, and worked my way through the documentation, but can find nothing to explain why views and clicks would not be tracked and reported.

Ads are set to display via Javascript and cache type is set to none. I tried toggling it on but that resulted in all the ads not being displayed.

The global settings status reports "Using detected adserve scripts: modules/ad/serve.php, modules/ad/adserve.inc" so I can't see a problem there.

I'd welcome any suggestions as to why there are no stats being recorded. Thank you.