Missing workflow detail in the WFTASK for a spend authorization

We have developed a custom BIP report, and report fetch the workflow details for spend authorization for all workflow approval scenarios. Its observed, there are for few authorization(s) only which is not storing the workflow details in the record (WFTASK), but for the same authorization it is visible in the application to whom workflow approval is triggered and approved by. Appreciate your help and support on to figure out the missing approval detail or table(s) to refer.

Below is the short query with mapping.

SELECT WFT.*
FROM
EXM_SPEND_AUTHORIZATIONS ESA,
FA_FUSION_SOAINFRA.WFTASK WFT
WHERE TO_CHAR(WFT.IDENTIFICATIONKEY) = TO_CHAR(ESA.SPEND_AUTHORIZATION_ID)