Learning withdrawal approval not working

We have a requirement where we would want to prevent learner from withdrawing from a Course (voluntary) where offering is selected and the offering “Withdrawal date” is in the past. We have configured a date type DFF at the offering level to capture the final withdrawal date.

We are trying to use below code for the above requirement, but it is returing a null error. Looks like when withdrawaing from a course it is unable to pick details from offering.

Approval Code

Duration.days between(Task.payload.Offering Specific Details.result.clsAttributeDate1.toGregorianCalendar(),CurrentDate.date) AND (Learning Item.result.Learning Item Type Code == "ORA_COURSE")