Datediff calculating some rows incorrectly but some correct???

[Ltbabyj]

I have the following DATEDIFF function with the results below that

Contract Variance = datediff('LAGUNA-Procore Activities'[Current Baseline],ScheduleTask[Earliest finish_datetime min per finish_datetime],day)

Some of these are correct but as you can see, most are not.  Any thoughts here?

[ryan_mayu]

is this a table visual?

what about try this

Contract Variance = datediff(MAX('LAGUNA-Procore Activities'[Current Baseline]),MAX(ScheduleTask[Earliest finish_datetime min per finish_datetime])),day)