Last modified date was not found in the query results error

Dear Experts,

While using SFAPI polling with parameter last_modified_on delta sync getting the below error.

"Last modified date was not found in the query results.This is needed for delta sync."

when i checked the SAP PI log, delta sync date is taking by the system as 1970-01-01.

Query i used is :

select description, externalCode, name, start_date

from FO_costCenter

where last_modified_on > to_datetime('${deltasync.maxDateFromLastRun}')

Please provide your inputs in resolving this issue.

Thanks & Regards,

Y V P Deepak