Invalid OADATE Value

Hi All!

I have received this error for the first time...I can't figure out what it is...all of my date fields are the correct type.  Here's the calc:

Capacity CALCULATION =

var Start_Date = min('DIM Calendar'[DateDate])
var End_Date = max('DIM Calendar'[DateDate])

//assuming DimBranch is connected to MDSFleetAttributes if I count the days fleetAttributes, which is filtered only to the branches selected, where I find the truck value located in carrier ref, then I know I can include that truck's capacity in the calc
RETURN

calculate(sumx('MDS FleetAttributes',if('MDS FleetAttributes'[TerminationDate]<End_Date,'MDS FleetAttributes'[TerminationDate],End_Date)-if('MDS FleetAttributes'[EffectiveDate]>=Start_Date,'MDS FleetAttributes'[EffectiveDate],Start_Date)* [Truck Capacity]),
 FILTER ('MDS FleetAttributes','MDS FleetAttributes'[EffectiveDate]<End_Date),('MDS FleetAttributes'[TerminationDate]>=Start_Date))

Calculated column in FleetAttributes:

Truck Capacity = CALCULATE(sum('Capacity Ref'[Capacity]),FILTER('Capacity Ref','Capacity Ref'[FleetUnitNumber]=EARLIER('MDS FleetAttributes'[FleetUnitNumber])))

What I'm trying to do is based on the report min/max date selected, what is the capacity of that truck multiplied by how long it resided at a specific branch within those dates

In the data set below my expected result would be:

If I select 2017-01-01 to 2017-03-01

Branch22425 = 18025*31

Branch 20031 = 18025*29

If I select both of the branches = 18025*60

For the purposed of this measureI I  have 4 tables:

Dim.Calendar

Dim.Branch - bu code

Capacity ref - aggregated table to get capacity average by fleetunitnumber

FleetUnitNumber Capacity

MDSFleetAttributes -

FleetUnitNumber BusinessUnitCode Capacity EffectiveDate TerminationDate

Hopefully, someone can see what is going on here!  Many thanks!!