Short answer: your tag is being prepared on the ad server, and that normally takes minutes — not hours. If a tag has shown "generating" for more than about an hour, retry it or create a new one; neither step affects anything already live.
What happens after you click Create tag
Creating a tag hands your rendered creative to the ad server (Campaign Manager 360 or Innovid), which transcodes it into its own serving formats and issues the tag. That's the "Ad tag is being generated" state. When it's ready, the tag appears on the creative's Versions & Tags tab and we email it to you.
If it's been more than an hour
Refresh the creative — the status shown can lag the ad server.
Check your inbox and spam folder for the tag email — it may have arrived even if the page didn't update.
Retry — open Versions & Tags and click Create tag again for the same version. Retrying is safe: it never alters a tag that's already trafficked.
Or create a fresh tag with Add ad tag — a new tag on the same creative, ready to traffic in place of the stalled one.
Still showing "generating"?
Message us in chat with the creative name or ID (Overview tab) and when you started it. We can see the ad-server job on our side and push it through or re-issue the tag — you won't lose anything you built.
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