diff --git a/disperser/apiserver/disperse_blob_v2.go b/disperser/apiserver/disperse_blob_v2.go
index 2e76d3a45..4e3e8ca7d 100644
--- a/disperser/apiserver/disperse_blob_v2.go
+++ b/disperser/apiserver/disperse_blob_v2.go
@@ -118,7 +118,7 @@ func (s *DispersalServerV2) validateDispersalRequest(ctx context.Context, req *p
 		return api.NewErrorInvalidArg("payment metadata is required")
 	}
 
-	if len(blobHeader.PaymentMetadata.AccountID) == 0 || (blobHeader.PaymentMetadata.ReservationPeriod == 0 && blobHeader.PaymentMetadata.CumulativePayment == nil) {
+	if len(blobHeader.PaymentMetadata.AccountID) == 0 || (blobHeader.PaymentMetadata.ReservationPeriod == 0 && blobHeader.PaymentMetadata.CumulativePayment.Cmp(big.NewInt(0)) == 0) {
 		return api.NewErrorInvalidArg("invalid payment metadata")
 	}
 
diff --git a/disperser/apiserver/server_v2_test.go b/disperser/apiserver/server_v2_test.go
index 367d3c9bb..305b6bd43 100644
--- a/disperser/apiserver/server_v2_test.go
+++ b/disperser/apiserver/server_v2_test.go
@@ -223,7 +223,7 @@ func TestV2DisperseBlobRequestValidation(t *testing.T) {
 		PaymentHeader: &pbcommon.PaymentHeader{
 			AccountId:         accountID,
 			ReservationPeriod: 0,
-			CumulativePayment: big.NewInt(100).Bytes(),
+			CumulativePayment: big.NewInt(0).Bytes(),
 		},
 	}
 	blobHeader, err := corev2.BlobHeaderFromProtobuf(invalidReqProto)