How to multiuply times the same type in request soap mock service groovy ?

How to send multiply time the same type in request soap mock services

 <invoiceDatas>
               <!--Zero or more repetitions:-->
               <invoiceData>
                  <id>?</id>
                  <MPK>?</MPK>
                  <RK>?</RK>
                  <value>?</value>
               </invoiceData>
            </invoiceDatas>

 i alwyas can send one row with this, but how to change to send for example 3 rows cans omeone explain in response i should have

 <invoiceDatas>
               <!--Zero or more repetitions:-->
               <invoiceData>
                  <id>?</id>
                  <MPK>?</MPK>
                  <RK>?</RK>
                  <value>?</value>
               </invoiceData>
  <!--Zero or more repetitions:-->
               <invoiceData>
                  <id>?</id>
                  <MPK>?</MPK>
                  <RK>?</RK>
                  <value>?</value>
               </invoiceData>
  <!--Zero or more repetitions:-->
               <invoiceData>
                  <id>?</id>
                  <MPK>?</MPK>
                  <RK>?</RK>
                  <value>?</value>
               </invoiceData>
            </invoiceDatas>

i have groovy script which looks that 

def holder = new com.eviware.soapui.support.XmlHolder( mockRequest.requestContent )
// get arguments
def fkId = Integer.parseInt( holder["//fkId"] )
def dateTime = holder["//dateTime"]
def status = holder["//status"]
def id = holder["//id"]
def MPK = holder["//MPK"]
def RK = holder["//RK"]

def value = holder["//value"]
def pid = Integer.parseInt( holder["//pid"] )
def type = holder["//type"]

def valueTotal = Float.parseFloat(holder["//valueTotal"])

//context.operationLogs += 'fkId: '+fkId + 'dateTime: '+ dateTime + 'status:' + status+' id: ' + id + 'MPK:'+ MPK +'RK:'+ RK + ' value:' + value +'pid:' + pid +'type:' + type + 'valueTotal:' + valueTotal

context.operationLogs += fkId

context.operationLogs1 += dateTime

context.operationLogs2 += status

context.operationLogs3 += id

context.operationLogs4 += MPK

context.operationLogs5 += RK

context.operationLogs6 += value

context.operationLogs7 += pid

context.operationLogs8 += type

context.operationLogs9 += valueTotal
requestContext.result1 = fkId

requestContext.result2 = dateTime

requestContext.result3 = status
requestContext.result4 = id
requestContext.result5 = MPK
requestContext.result6 = RK
requestContext.result7 = value
requestContext.result8 = pid
requestContext.result9 = type
requestContext.result10 = valueTotal
requestContext.result = [fkId, dateTime,status,id,MPK,RK,value,pid,valueTotal ]

context.fkId = context.operationLogs.size

context.fkId = context.operationLogs1.size

context.fkId = context.operationLogs2.size

context.fkId = context.operationLogs3.size

context.fkId = context.operationLogs4.size

context.fkId = context.operationLogs5.size

context.fkId = context.operationLogs6.size

context.fkId = context.operationLogs7.size

context.fkId = context.operationLogs8.size

context.fkId = context.operationLogs9.size

 my response is thaht 

<ResponseMessageAdd>
<fkId>${result}</fkId>
<dateTime>${result1}</dateTime>
<status>${result2}</status>
<invoiceDatas>
<!--Zero or more repetitions:-->
<invoiceData>
<id>${result3}</id>
<MPK>${result4}</MPK>
<RK>${result5}</RK>
<value>${result6}</value>
</invoiceData>
<invoiceData>
<id>${result3}</id>
<MPK>${result4}</MPK>
<RK>${result5}</RK>
<value>${result6}</value>
</invoiceData>

</invoiceDatas>
<payments>
<pid>${result7}</pid>
<type>${result8}</type>
<valueTotal>${result9}</valueTotal>
</payments>
</ResponseMessageAdd>
<!--Optional:-->
<Reference>${result}</Reference>