diff --git a/src/main/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessor.java b/src/main/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessor.java
index 736fecafc..482a8730c 100644
--- a/src/main/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessor.java
+++ b/src/main/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessor.java
@@ -105,7 +105,7 @@ public void execute(IngestDocument ingestDocument, BiConsumer<IngestDocument, Ex
                 handler.accept(ingestDocument, null);
             } else {
                 mlCommonsClientAccessor.inferenceSentences(this.modelId, inferenceList, ActionListener.wrap(vectors -> {
-                    appendVectorFieldsToDocument(ingestDocument, knnMap, vectors);
+                    setVectorFieldsToDocument(ingestDocument, knnMap, vectors);
                     handler.accept(ingestDocument, null);
                 }, e -> { handler.accept(null, e); }));
             }
@@ -115,11 +115,11 @@ public void execute(IngestDocument ingestDocument, BiConsumer<IngestDocument, Ex
 
     }
 
-    void appendVectorFieldsToDocument(IngestDocument ingestDocument, Map<String, Object> knnMap, List<List<Float>> vectors) {
+    void setVectorFieldsToDocument(IngestDocument ingestDocument, Map<String, Object> knnMap, List<List<Float>> vectors) {
         Objects.requireNonNull(vectors, "embedding failed, inference returns null result!");
         log.debug("Text embedding result fetched, starting build vector output!");
         Map<String, Object> textEmbeddingResult = buildTextEmbeddingResult(knnMap, vectors, ingestDocument.getSourceAndMetadata());
-        textEmbeddingResult.forEach(ingestDocument::appendFieldValue);
+        textEmbeddingResult.forEach(ingestDocument::setFieldValue);
     }
 
     @SuppressWarnings({ "unchecked" })
diff --git a/src/test/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessorTests.java b/src/test/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessorTests.java
index d4a92f103..b406030f0 100644
--- a/src/test/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessorTests.java
+++ b/src/test/java/org/opensearch/neuralsearch/processor/TextEmbeddingProcessorTests.java
@@ -350,7 +350,7 @@ public void testProcessResponse_successful() throws Exception {
         Map<String, Object> knnMap = processor.buildMapWithKnnKeyAndOriginalValue(ingestDocument);
 
         List<List<Float>> modelTensorList = createMockVectorResult();
-        processor.appendVectorFieldsToDocument(ingestDocument, knnMap, modelTensorList);
+        processor.setVectorFieldsToDocument(ingestDocument, knnMap, modelTensorList);
         assertEquals(12, ingestDocument.getSourceAndMetadata().size());
     }
 
@@ -398,6 +398,20 @@ public void testBuildVectorOutput_withNestedMap_successful() {
         assertNotNull(actionGamesKnn);
     }
 
+    public void test_updateDocument_appendVectorFieldsToDocument_successful() {
+        Map<String, Object> config = createPlainStringConfiguration();
+        IngestDocument ingestDocument = createPlainIngestDocument();
+        TextEmbeddingProcessor processor = createInstanceWithNestedMapConfiguration(config);
+        Map<String, Object> knnMap = processor.buildMapWithKnnKeyAndOriginalValue(ingestDocument);
+        List<List<Float>> modelTensorList = createMockVectorResult();
+        processor.setVectorFieldsToDocument(ingestDocument, knnMap, modelTensorList);
+
+        List<List<Float>> modelTensorList1 = createMockVectorResult();
+        processor.setVectorFieldsToDocument(ingestDocument, knnMap, modelTensorList1);
+        assertEquals(12, ingestDocument.getSourceAndMetadata().size());
+        assertEquals(2, ((List<?>) ingestDocument.getSourceAndMetadata().get("oriKey6_knn")).size());
+    }
+
     private List<List<Float>> createMockVectorResult() {
         List<List<Float>> modelTensorList = new ArrayList<>();
         List<Float> number1 = ImmutableList.of(1.234f, 2.354f);