# ParentSegmentNotFoundException ## Format ParentSegmentNotFoundException
expected: PARENT_SEGMENT_EXPRESS
actual: NOT FOUND ## Cause The `ParentSegmentNotFoundException` caused by the parent segment express cannot found in the actual data file.
e.g., expected: ``` "refs": [ { "parentTraceSegmentId": "${other_application[10]}", ... } ] ``` actual: The segment size of `other_application` less than 10 ## Check Points 1. Check if the parent segment express is correct