Spock test not working as expected

I have a service class in grails that I'm testing which is giving me a strange message that I don't understand ..

In my test I have ..

  expect:
        validationRequest.every{
             def result = service.validateStillageContent(it)
             println "\nresult ->${result}"
             result} instanceof ValidationResponse

 where:
       validationRequest | returnValue     | validationType
       new ValidationRequest(validationType:"serialPart")    | "OK"   |     "serialPart"

which is giving me this ..

Condition not satisfied: validationRequest.every{ def result =     service.validateStillageContent(it) println "\nresult ->${result}" result}

instanceof ValidationResponse | | | | true false ValidationRequest{validationType='serialPart', documentReference='null', partNumber='null', altPartNumber='null', vendorPartNumber='null', serialNumber='null', stillage='null', ducketReference='null', sequence=null}

and

junit.framework.AssertionFailedError: Condition not satisfied:

validationRequest.every{ def result = service.validateStillageContent(it) println "\nresult ->${result}" result}
instanceof ValidationResponse |                                                                                                    |

| true false ValidationRequest{validationType='serialPart', documentReference='null', partNumber='null', altPartNumber='null', vendorPartNumber='null', serialNumber='null', stillage='null', ducketReference='null', sequence=null}

at com.dev.SequencingServiceSpec.Test the stillage validation with various types  .. (SequencingServiceSpec.groovy:254)

and

result ->ValidationResponse{status='OK', errorMessage='null'}

There are more entries in my table but they all exhibit the same problem .. As I see it the service call results in an instance of ValidationResponse but the test is giving me a "condition not satisfied" .. Can someone explain why ?

Thanks