Some data not found

What causes this issue?

The system tried to read all segment types for IDoc type &v1& and
Release &v2&.

System Response

Not all segments were already defined for the specified Release &v2&.
The transferred data is therefore not valid for all segments from the
release in question onwards. If a segment type had not yet been defined
for the release in question, the first release with this type was
determined and the first segment definitions from that release were
transferred.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.