diff --git a/api/src/main/java/uk/gov/hmcts/payment/api/dto/mapper/PaymentDtoMapper.java b/api/src/main/java/uk/gov/hmcts/payment/api/dto/mapper/PaymentDtoMapper.java
index f0bb563a51..909a2c59ea 100644
--- a/api/src/main/java/uk/gov/hmcts/payment/api/dto/mapper/PaymentDtoMapper.java
+++ b/api/src/main/java/uk/gov/hmcts/payment/api/dto/mapper/PaymentDtoMapper.java
@@ -344,7 +344,7 @@ public PaymentDto toReconciliationResponseDtoForLibereta(final Payment payment,
         LOG.info("apportionCheck value in PaymentDtoMapper: {}",apportionCheck);
         PaymentDto paymentDto = PaymentDto.payment2DtoWith()
             .paymentReference(payment.getReference())
-            .paymentGroupReference(apportionCheck ? null : paymentReference)
+            .paymentGroupReference(paymentReference)
             .serviceName(payment.getServiceType())
             .siteId(payment.getSiteId())
             .amount(payment.getAmount())
diff --git a/api/src/main/java/uk/gov/hmcts/payment/api/service/IacServiceImpl.java b/api/src/main/java/uk/gov/hmcts/payment/api/service/IacServiceImpl.java
index 50d8b4bca4..80c5fa7377 100644
--- a/api/src/main/java/uk/gov/hmcts/payment/api/service/IacServiceImpl.java
+++ b/api/src/main/java/uk/gov/hmcts/payment/api/service/IacServiceImpl.java
@@ -22,6 +22,7 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 @Service
@@ -96,13 +97,17 @@ public ResponseEntity<SupplementaryPaymentDto> getIacSupplementaryInfo(List<Paym
     @Override
     public void updateCaseReferenceInPaymentDtos(List<PaymentDto> paymentDtos, String serviceName) {
         List<PaymentDto> iacPayments = getIacPayments(serviceName, paymentDtos);
+
         iacPayments.forEach(paymentDto ->
-            paymentFeeLinkRepository.findByCcdCaseNumber(paymentDto.getCcdCaseNumber()).ifPresent(paymentFeeLinks ->
-                paymentFeeLinks.stream().filter(paymentLink -> paymentDto.getCaseReference() == null && paymentLink.getCaseReference() != null).findFirst().ifPresent(paymentLink -> {
-                    paymentDto.setCaseReference(paymentLink.getCaseReference());
-                    LOG.info("Setting caseReference {} from paymentFeeLink for CCD Case {}", paymentLink.getCaseReference(), paymentDto.getCcdCaseNumber());
-                })
-            )
+            paymentFeeLinkRepository.findByPaymentReference(paymentDto.getPaymentGroupReference()).ifPresent(paymentFeeLink -> {
+                if (paymentDto.getCaseReference() == null && paymentFeeLink.getCaseReference() != null && paymentFeeLink.getCaseReference().length() > 0) {
+                    paymentDto.setCaseReference(paymentFeeLink.getCaseReference());
+                    LOG.info("Setting caseReference {} for Service Request {} in Case {}",
+                        paymentFeeLink.getCaseReference(),
+                        paymentDto.getPaymentGroupReference(),
+                        paymentDto.getCcdCaseNumber());
+                }
+            })
         );
     }
 
diff --git a/api/src/test/java/uk/gov/hmcts/payment/api/service/IacServiceTest.java b/api/src/test/java/uk/gov/hmcts/payment/api/service/IacServiceTest.java
index 4d98fc879f..8b38b423d8 100644
--- a/api/src/test/java/uk/gov/hmcts/payment/api/service/IacServiceTest.java
+++ b/api/src/test/java/uk/gov/hmcts/payment/api/service/IacServiceTest.java
@@ -46,6 +46,7 @@ public class IacServiceTest {
     @Before
     public void setUp() {
         paymentDto =  PaymentDto.payment2DtoWith()
+            .paymentGroupReference("2024-1706099566733")
             .paymentReference("RC-2222-3333-4444-5555")
             .ccdCaseNumber("1111-2222-3333-4444")
             .caseReference(null)
@@ -80,10 +81,10 @@ public void getIacSupplementaryInfoHttpClientErrorException() {
     }
 
     @Test
-    public void updateCaseReferenceInPaymentDtosSuccess() {
+    public void updateCaseReferenceInPaymentDtoFeeLinksSuccess() {
         List<PaymentDto> paymentDtos = Collections.singletonList(paymentDto);
-        PaymentFeeLink paymentFeeLink = PaymentFeeLink.paymentFeeLinkWith().ccdCaseNumber("1111-2222-3333-4444").caseReference("IAC/1234/REF").build();
-        when(paymentFeeLinkRepository.findByCcdCaseNumber("1111-2222-3333-4444")).thenReturn(Optional.of(Collections.singletonList(paymentFeeLink)));
+        PaymentFeeLink paymentFeeLink = PaymentFeeLink.paymentFeeLinkWith().paymentReference("2024-1706099566733").caseReference("IAC/1234/REF").build();
+        when(paymentFeeLinkRepository.findByPaymentReference("2024-1706099566733")).thenReturn(Optional.of(paymentFeeLink));
 
         iacService.updateCaseReferenceInPaymentDtos(paymentDtos, IAC_SERVICE_CODE);
 
@@ -91,30 +92,27 @@ public void updateCaseReferenceInPaymentDtosSuccess() {
     }
 
     @Test
-    public void updateCaseReferenceInPaymentDtosMultipleFeeLinksSuccess() {
+    public void updateCaseReferenceInPaymentDtosIgnoredAsAlreadyPopulated() {
+        paymentDto.setCaseReference("IAC/1234/REF");
         List<PaymentDto> paymentDtos = Collections.singletonList(paymentDto);
-        PaymentFeeLink paymentFeeLink1 = PaymentFeeLink.paymentFeeLinkWith().ccdCaseNumber("1111-2222-3333-4444").build();
-        PaymentFeeLink paymentFeeLink2 = PaymentFeeLink.paymentFeeLinkWith().ccdCaseNumber("1111-2222-3333-4444").build();
-        PaymentFeeLink paymentFeeLink3 = PaymentFeeLink.paymentFeeLinkWith().ccdCaseNumber("1111-2222-3333-4444").caseReference("IAC/1234/REF").build();
-        PaymentFeeLink paymentFeeLink4 = PaymentFeeLink.paymentFeeLinkWith().ccdCaseNumber("1111-2222-3333-4444").build();
-        List<PaymentFeeLink> paymentFeeLinks = List.of(paymentFeeLink1, paymentFeeLink2, paymentFeeLink3, paymentFeeLink4);
-        when(paymentFeeLinkRepository.findByCcdCaseNumber("1111-2222-3333-4444")).thenReturn(Optional.of(paymentFeeLinks));
+        PaymentFeeLink paymentFeeLink = PaymentFeeLink.paymentFeeLinkWith().caseReference("IAC/6789/REF").build();
+        when(paymentFeeLinkRepository.findByPaymentReference(anyString())).thenReturn(Optional.of(paymentFeeLink));
 
         iacService.updateCaseReferenceInPaymentDtos(paymentDtos, IAC_SERVICE_CODE);
 
         assertEquals("IAC/1234/REF", paymentDto.getCaseReference());
     }
 
+
     @Test
-    public void updateCaseReferenceInPaymentDtosIgnoredAsAlreadyPopulated() {
-        paymentDto.setCaseReference("IAC/1234/REF");
+    public void updateCaseReferenceInPaymentDtosEmptyCaseReference() {
         List<PaymentDto> paymentDtos = Collections.singletonList(paymentDto);
-        PaymentFeeLink paymentFeeLink = PaymentFeeLink.paymentFeeLinkWith().caseReference("IAC/6789/REF").build();
-        when(paymentFeeLinkRepository.findByCcdCaseNumber(anyString())).thenReturn(Optional.of(Collections.singletonList(paymentFeeLink)));
+        PaymentFeeLink paymentFeeLink = PaymentFeeLink.paymentFeeLinkWith().paymentReference("2024-1706099566733").caseReference("").build();
+        when(paymentFeeLinkRepository.findByPaymentReference("2024-1706099566733")).thenReturn(Optional.of(paymentFeeLink));
 
         iacService.updateCaseReferenceInPaymentDtos(paymentDtos, IAC_SERVICE_CODE);
 
-        assertEquals("IAC/1234/REF", paymentDto.getCaseReference());
+        assertEquals(null, paymentDto.getCaseReference());
     }
 
     @Test