> 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/no-data/historical-backfill-returns-nothing/historical-backfill-endpoints-and-gaps.md).

# Can I backfill missing historical data?

**Yes.** For cloud-API providers, missing past data can be retroactively pulled using the [historical data request endpoints](https://docs.tryterra.co/health-and-fitness-api/managing-user-health-data/requesting-historical-data) (e.g. `/v2/daily`, `/v2/activity`) with the date range and `to_webhook=true` to replay it into your destination.

Gaps are usually caused by:

* Temporary webhook-delivery interruptions on the platform or provider side.
* Providers occasionally never sending a webhook for an event.

**Report multi-day gaps** so a backfill can be run for affected users.