> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/faq/help-topics/data-api-sdk/webhooks-dedup-and-sync-reliability/timezone-date-boundary-missing-day.md).

# Why does a daily payload look missing for one day?

**This is a timezone boundary effect, not missing data.** When a user is in a non-UTC timezone, a day's daily payload can have a UTC `start_time` that falls on the previous (or next) calendar day, so a query keyed to the local date can miss it.

How to handle it:

* **Expand your query date range by one day on each side**, then filter on your side using the timezone offset in the metadata to determine the actual local date.
* For daily, body, and nutrition events (which span midnight-to-midnight calendar days), use only the **date part** of `start_time` as your record identifier, rather than the full timestamp.
* When a provider does not supply a UTC offset, Terra omits it rather than sending a false one.

If you need to pause ingestion to migrate, **return an error code (for example, 502)** so webhooks are retried later rather than dropped. See [receiving data updates](https://docs.tryterra.co/health-and-fitness-api/managing-user-health-data/receiving-data-updates) for retry behaviour.