Hi @Bharath Vadlamannati，
Check the Error Output (under Connection Manager and Mappings) within Destination Component. If the Error setting is set to Ignore Failure or Redirect Row, the component will succeed, but only the successful rows will be inserted.
And also check the destination file and make sure it could store the acceptable number of rows.
You may also preview the source data to ensure the Connection Manager Source has no issue.
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