Why do I get "LinkID not found" when when Querying HERE API v1

Symptoms
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You may encounter one or more of the following situations when working with HERE map data APIs:

An API response returns a valid LinkID, but a subsequent request using the same LinkID fails with a "LinkID not found" error.
Queries that previously worked with a stored LinkID begin failing after a map data update.
A road segment appears to exist on the map, but requests using the corresponding historical LinkID return no results.
Applications that persist LinkID values for long periods experience intermittent lookup failures.

Answer
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A LinkID is an internal identifier used by HERE map data to represent a road segment (link). LinkIDs are not guaranteed to remain unchanged across map releases and may differ between products, services, or map versions. If a LinkID was generated from one map version and later used against a different map version, the service may return a "LinkID not found" error.

Root Cause
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HERE map content is continuously updated to reflect changes in the real world. As part of these updates:

Road geometry can be modified.
Road segments can be split, merged, or replaced.
Internal identifiers, including LinkID values, can change.

Because of this, a LinkID should not be treated as a permanent or globally reusable identifier. In addition, different HERE APIs may use different underlying map versions. A LinkID retrieved from one API response may therefore not exist in another API's dataset.

Impact
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Applications that store and reuse LinkIDs may experience:

Failed lookups
Missing road segment information
Inconsistent results across different APIs
Errors after map data updates

Recommended Actions
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To avoid LinkID lookup failures:

1. Use LinkIDs only within the context of the map version that generated them.
2. Avoid storing and reusing LinkIDs for long periods of time.
3. Do not assume that a LinkID returned by one HERE API can be queried successfully in another HERE API.
4. When possible, retrieve current identifiers from the latest API response instead of relying on previously stored values.
5. Validate that the source and target services are using compatible map data versions before performing LinkID-based lookups.

Expected vs. Unexpected Behavior
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### Expected Behavior

A LinkID is valid only within the map data context in which it was generated.
A LinkID may change after map data updates.
A LinkID from one API may not be recognized by another API using a different map version.

### Unexpected Behavior

A recently generated LinkID fails within the same request workflow while using the same dataset and map version.
A LinkID lookup fails despite confirmed map version alignment between all involved services.

If the unexpected behavior occurs, collect API request and response details and verify map version compatibility before further investigation.

Additional Information
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For technical details about HERE LinkIDs, see the official documentation:

HERE Link ID Documentation

Keywords
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LinkID, Link ID not found, HERE Maps, map version, road segment identifier, link lookup failure, map data update, routing data, map content changes, API compatibility, segment ID, geospatial data, HERE platform, location services, map identifiers