Sum Values Based on Multiple Entries from Multiple Columns

Anonymous you can use a measure like this

Measure= CALCULATE(SUM(tbl[Subtotal]), ALLEXCEPT(tbl,tbl[Device ID],tbl[Day]))

Anonymous  when all the axis comes form Scanner Stats

Measure =
CALCULATE (
    SUM ( ScannerStats[Subtotal] ),
    ALLEXCEPT ( ScannerStats, ScannerStats[DeviceId], ScannerStats[Date] )
)

when axis come from different tables

Measure2 =
CALCULATE (
    SUM ( ScannerStats[Subtotal] ),
    VALUES ( ScannerStats[DeviceId] ),
    VALUES ( DateTable[Date] )
)

pbix is attached