Meta Conversions API not working: a checklist for common failures
Troubleshooting guide · 2 min read · Updated 2026-10-21 · By the Cofoundr team
When Conversions API events do not appear, check the dataset and access token, then the event name and event time, then the required parameters, and use Test Events to see the exact error. If events arrive but numbers look doubled, the problem is de-duplication with the browser pixel, not delivery.
The Conversions API sends events from your server to Meta. Failures are usually small and visible in Events Manager once you know where to look. Meta changes details over time, so confirm field requirements in its current developer documentation.
1. Use Test Events first
Send a test event with the test code from Events Manager and watch the response. The error message usually names the problem.
2. Dataset and access token
- Are you sending to the right dataset or pixel ID?
- Is the access token valid, and does it have permission for this dataset?
- Did the token expire or get revoked when someone left the business?
3. Event details
- Is the event name one Meta recognises, spelled exactly?
- Is the event time recent and in the right format? Meta limits how old an event can be.
- For purchases, are value and currency present?
4. Customer parameters
Events need enough customer information to be matched, hashed the way Meta requires. Missing or badly formatted values lower matching. See event match quality low.
5. Partner and platform integrations
- If an e-commerce or tag platform sends events for you, check its connection and logs.
- A platform and a custom integration sending together causes duplicates.
6. De-duplication
If you also run the browser pixel, share an event name and event ID across both. See duplicate conversions.
How Cofoundr helps
Cofoundr does not connect to your Conversions API setup. It reads the results Meta reports, so a drop in conversions or a gap between clicks and results shows up on the client page and in alerts for zero results.
Frequently asked questions
Why are my Conversions API events not showing?
Check the dataset and access token, the event name and time, and the required parameters, and use Test Events for the exact error.
Do I need both the pixel and the Conversions API?
Many setups use both, with shared event IDs for de-duplication. Check Meta's guidance for your case.
How long until events appear?
Test events show quickly. Reports can lag, so compare over a day or more.