The report claims the GA4 tag doesn't work, and you know it's on the site? This is the most nuanced troubleshooting scenario - because both sides can be right at once. The scanner visits the site like a real user, so it sees what an anonymous first visit sees. The typical mismatches:
1. The consent banner blocks the tag before consent
The most common cause - and often a correct diagnosis, not a false alarm. If your cookie banner doesn't load GA4 at all before consent (hard blocking instead of Consent Mode), then every new user is invisible to analytics until they click "accept". The scanner simulates consent scenarios and reports the behavior - if the tag works in none of them, or vanishes entirely pre-consent, you'll see it in the results. The solution is a correct Consent Mode v2 implementation (cookieless pings before consent), not "fixing the scanner".
2. The tag loads with a long delay
Tags injected after a long delay (performance optimizations, lazy-loaded scripts, some site builders) can fall outside the scanner's observation window. The side effect in GA4: undercounted page_views from short visits - because real users also "escape" before the tag loads.
3. Anti-bot protections block the scanner
A WAF, Cloudflare challenges or aggressive bot-protection rules can cut off the scanner's visit before the page loads. Site-verified checkpoints then receive "N/A" with a note - and you can verify them manually (how).
4. The tag exists but sends to a different property
The scanner detects the measurement IDs on the page and compares them with the audited property. If the site runs a G-OTHER123 tag while you audit the property with G-YOURS456 - the report rightly flags a problem. A classic after migrations and with several similarly named properties (how not to mix them up).
5. Server-side implementations
With server-side tagging (sGTM), the in-browser picture differs from a standard setup - some signals the scanner looks for travel a different route; browser-verified checkpoints may then require manual verification.
How to verify yourself in 5 minutes
If after this verification you believe the report is wrong - report it to us: how to report an audit issue.
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