Multiple filters in DAX

NSSLynne ,

Believe your syntax for using SUMX is incorrect.  Please try this:

Spec3£1 = 
    SUMX( FILTER('POD Report','POD Report'[Site Attended?] = "Site attended but no work carried out - Customer Fault" || ('POD Report'[Site Attended?] = "Yes" && 'POD Report'[3. Spec Done?] = "Yes")),
    [3. Spec Price] )

Or I think you can simply use SUM:

Spec3£1_SUM = CALCULATE(
    SUM( 'POD Report'[3. Spec Price]),
    FILTER('POD Report','POD Report'[Site Attended?] = "Site attended but no work carried out - Customer Fault" || ('POD Report'[Site Attended?] = "Yes" && 'POD Report'[3. Spec Done?] = "Yes")))

to perhaps achieve the same result.

Hope one of these provides a solution to your issue:

Regards,