My slug is unavailable
Someone (possibly you) is already using it on that domain.
Slugs are unique per domain, so a slug that's taken means someone - possibly a different link of yours - is already using it on that specific domain. Try a different slug, or pick a different domain; the same slug can exist separately on golo.to and on each of your custom domains. See What happens if a slug is already taken?
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Analytics are delayed - Expected lag, not lost data.
My analytics isn't updating - Give it a few minutes - dashboard views can lag slightly.
My analytics look wrong - Clicks not showing, delayed data, or numbers that don't match another tool.
Attribution isn't working - Usually means the link isn't attached to the video yet.