Your Meta pixel fires on the page - Tag Assistant confirms it - but Events Manager shows nothing. Or events appear in Events Manager and never make it into Ads Manager reporting. Or both show numbers, but the totals are a fraction of what your CRM records.
These are three distinct problems. Most diagnostics treat them as one and miss the cause. This guide separates them and works through all 12 causes in the order that finds most issues fastest. Updated for the April 2026 AEM priority changes and the Andromeda deduplication regression.
Before You Start: What "Not Tracking" Actually Means
Three different problems get called "pixel not tracking."
Problem 1. Pixel fires on the page but events never appear in Events Manager, even in Test Events. This is a collection failure - nothing is reaching Meta.
Problem 2. Events appear in Events Manager but not in Ads Manager reporting. Collection is working; the data is being filtered or blocked before it feeds into campaign reporting.
Problem 3. Events appear in both but conversions are dramatically under-counted relative to your CRM or backend. Collection is partial - a structural gap in the data path.
The 12-step diagnostic below is ordered to surface Problem 1 first, then Problem 2, then Problem 3. Most operators resolve the issue within the first four checks.
The 12-Step Diagnostic
Cause 1: Base Code Not Installed Correctly
Symptom. No events at all in Events Manager, even after browsing the site in a logged-out browser.
Fix. Open an incognito window and navigate to your site. Open Tag Assistant and confirm the base pixel code is firing. If it is not, the code is missing, placed incorrectly, or blocked by a Content Security Policy header. Re-install via GTM or directly in the page <head>, following Meta's current installation docs. Check the CSP header for connect.facebook.net - if it is not in the connect-src directive, the pixel request is blocked before it leaves the browser.
Cause 2: Event Code on the Wrong Page
Symptom. PageView fires (Tag Assistant shows green), but Purchase or Lead events never appear.
Fix. Navigate to the actual conversion page - the thank-you page, order confirmation, or form success screen. Inspect the page source and verify the conversion event code is present. In GTM setups, conversion tags commonly fire on a URL-match trigger. If the thank-you page URL changed (a Shopify theme update, a checkout platform migration), the trigger no longer matches and the event never fires.
Cause 3: Aggregated Event Measurement Priority Not Configured
Symptom. Events fire and appear in Events Manager > Test Events, but they never appear in Events Manager > Overview or in Ads Manager campaign reporting.
Fix. Open Events Manager, select your pixel, go to Settings > Aggregated Event Measurement. Verify your conversion events are listed and prioritized. Events not in the AEM priority list are filtered out for iOS users who have opted out of tracking. This is the leading cause we see in 2026 audits. If your Purchase or Lead event is not in the top 8, it will never appear in Ads Manager for a significant portion of your audience.
Cause 4: Conversion API event_id Mismatch
Symptom. Events appear in Events Manager but conversion counts look inflated (double-counting) or deflated.
Fix. Open Events Manager > Test Events. Send a test event from your browser pixel and the same event from your CAPI implementation, using the same event_id. Check the Deduplication Score - it should sit at 80% or above. A common source of this bug: the pixel generates event_id using Date.now() or a client-side random value, while CAPI generates a different ID from the server. The two events look identical to Meta except for the ID, so deduplication does not trigger and both are counted.
Cause 5: Ad Blockers Stripping the Pixel
Symptom. Pixel works correctly in your development browser but conversions are missing for a chunk of real traffic.
Fix. Open a clean browser profile with uBlock Origin or Brave's shield enabled and attempt a test conversion. If the pixel does not fire, that traffic segment is completely invisible to client-side collection. The structural fix is Conversion API - server-side events cannot be blocked by browser extensions. For the scope of the problem: roughly 30% of desktop browsers in 2026 run some form of ad blocking that targets connect.facebook.net.
Cause 6: iOS Opt-Out With No CAPI Fallback
Symptom. Conversions appear in your CRM but not in Events Manager. The gap is concentrated on iOS users.
Fix. Implement Conversion API for server-side event delivery. iOS users who opted out of tracking under ATT are invisible to browser-based pixel collection. As of 2026, over 50% of iOS users have opted out. Without a server-side path, the majority of your mobile conversions never reach Meta. CAPI combined with correct AEM priority configuration is the minimum viable setup for any campaign with meaningful iOS traffic.
Cause 7: Cross-Domain Attribution Broken
Symptom. Pixel fires correctly on your main storefront but conversions on a separate checkout domain are not tracked back to ad campaigns.
Fix. If your checkout lives on a separate domain - a Recharge subdomain, a Bold Commerce instance, a custom payment processor - the pixel installed on the main domain cannot follow the user there. You have two options: install the pixel directly on the checkout domain, or implement CAPI from your checkout system's server. Most major third-party checkout platforms offer native CAPI integration but require manual configuration to activate it.
Cause 8: GTM Container Missing on Conversion Page
Symptom. Pixel fires on all standard pages but never fires on the thank-you or order confirmation page specifically.
Fix. Open the thank-you page source and search for your GTM container ID. If it is absent, that page lives outside GTM's scope. This is common on Shopify and WooCommerce, where the checkout and order confirmation flow is controlled separately by the platform. Shopify requires pixel installation through its own Customer Events settings; it does not inherit GTM tags from the theme.
Cause 9: Custom Event Parameters Formatted Incorrectly
Symptom. Events fire and appear in Events Manager but value, currency, or content_ids show as missing or malformed in the event detail view.
Fix. Open Events Manager > Test Events, select the event, and inspect the Parameters panel. Verify:
valueis a number -29.99, not the string"29.99 USD"currencyis a 3-letter ISO code -"USD", not"$"content_idsis an array -["SKU-123"], not a string
Meta's Smart Bidding cannot optimize toward events with malformed parameters even when the event count appears correct. The data is received but cannot be used.
Cause 10: Account-Level Pixel Disapproval
Symptom. Pixel works correctly in Test Events. Events do not appear in Ads Manager reporting. No visible error in Events Manager.
Fix. Go to Business Settings > Data Sources > Pixels and check for any "Disapproved" or "Restricted" status on the pixel. Some accounts encounter this after a policy review - the pixel continues collecting data, but the ad system is blocked from using it for campaign optimization. The path forward is an appeal through the Business Help Center. Filing through the Meta Ads support form with screenshots of correct event activity accelerates the review.
Cause 11: AEM Priority List Capped at 8
Symptom. You are tracking more than 8 events and some conversions are inconsistently missing for iOS users with no other obvious cause.
Fix. Open Events Manager > Aggregated Event Measurement settings. The AEM system allows a maximum of 8 prioritized events per pixel. Any event beyond position 8 is silently dropped for iOS opt-out users - no error is shown, no warning is issued. The fix is not to add more events; it is to choose which 8 matter most and remove the rest from the priority list.
Cause 12: Andromeda Deduplication Regression (April 2026)
Symptom. Issue started after April 1, 2026. Both pixel and CAPI are sending events correctly, but the Deduplication Score in Events Manager has dropped below 50%.
Fix. First verify the basics: event_id is consistent between pixel and CAPI, and CAPI requests include both fbp and fbc cookie values from the browser. If both are correct and the score remains degraded, this is a known regression on Meta's side introduced in the April 2026 Andromeda infrastructure update. File a support ticket referencing the April 2026 Andromeda deduplication regression, include your pixel ID, and attach screenshots showing the Deduplication Score and your CAPI event log.
When to File a Meta Support Ticket
Run the full 12-step diagnostic before opening a ticket. Meta support cannot act on "conversions are missing" - they need specific evidence.
File a ticket when:
- All 12 checks pass and events are still not appearing after 24 hours
- Business Settings shows a "Pixel disapproved" or "Restricted" status
- You are experiencing the April 2026 Andromeda dedup regression with a score below 50% despite correct
event_idand cookie configuration - Test Events show correct pixel events that do not appear in Ads Manager after 24 hours
When you open the ticket, have ready: your pixel ID, screenshots of the Test Events panel showing the event firing, screenshots of the Deduplication Score, and the event_id values used in both pixel and CAPI calls. Tickets with this evidence resolve significantly faster than those without it.
Do not file a ticket before checking AEM priority - this wastes your support queue position and delays resolution. Do not make changes to your pixel implementation while a ticket is open; it resets the diagnostic baseline and makes it harder for Meta's team to reproduce the issue.
The Minimum Healthy Tracking Setup in 2026
A pixel alone is no longer sufficient. The combination that covers the structural gaps is:
- Browser pixel with correct base code and conversion events on the right pages
- Conversion API running server-side, sending events with hashed first-party data
event_iddeduplication wiring both paths together- AEM priority list configured to your top 8 conversion events
Most of the issues in this diagnostic are either a missing piece of that setup or a misconfiguration in one of its components. The diagnostic exists to find which one.