The scan ended with an error, or the progress bar has been frozen for more than a few minutes? Walk this path - ordered from the most common cause.
1. The GA4 session expired (by far the most common)
A message like "Your GA4 connection session has expired or no property was selected" means the Google token (valid ~1 h) expired between connecting and scanning. The fix: Reconnect to GA4 and run the audit again. The mechanism: GA4 session expired. A variant of the same problem: the audit "succeeded" but every checkpoint shows no access - what then.
2. The scan is genuinely running - give it a moment
An audit usually takes 1-3 minutes, but large properties and slow-loading websites can stretch it (what affects the time). If the progress bar moves between stages - wait. Intervene when it sits on one stage for clearly longer than a few minutes.
3. You closed the tab / interrupted the process
An interrupted scan? Simply run it again - a rescan next to the project or a new audit from the wizard. An unfinished scan breaks nothing.
4. The sign-in session expired at save time
The "Your session expired - sign in again to save the audit" message concerns your GA4audit sign-in (not the GA4 connection). Sign in again and repeat the scan.
5. The generic "Audit failed" error
Does a failed scan consume a limit?
On paid plans, limits concern projects, not audits - a failed scan "burns" nothing. On the Free plan a stored report is what counts: if a failed scan managed to save an empty entry, delete it from the history - the limit frees up.
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