diff --git a/src/main/java/org/opensearch/securityanalytics/logtype/LogTypeService.java b/src/main/java/org/opensearch/securityanalytics/logtype/LogTypeService.java
index 243b95043..a31e294e1 100644
--- a/src/main/java/org/opensearch/securityanalytics/logtype/LogTypeService.java
+++ b/src/main/java/org/opensearch/securityanalytics/logtype/LogTypeService.java
@@ -346,19 +346,27 @@ private List<FieldMappingDoc> mergeFieldMappings(List<FieldMappingDoc> existingF
         List<FieldMappingDoc> newFieldMappings = new ArrayList<>();
         fieldMappingDocs.forEach( newFieldMapping -> {
             Optional<FieldMappingDoc> foundFieldMappingDoc = Optional.empty();
-            for (FieldMappingDoc e: existingFieldMappings) {
-                if (e.getRawField().equals(newFieldMapping.getRawField())) {
+            for (FieldMappingDoc existingFieldMapping: existingFieldMappings) {
+                if (existingFieldMapping.getRawField().equals(newFieldMapping.getRawField())) {
                     if ((
-                            e.get(defaultSchemaField) != null && newFieldMapping.get(defaultSchemaField) != null &&
-                                    e.get(defaultSchemaField).equals(newFieldMapping.get(defaultSchemaField))
+                            existingFieldMapping.get(defaultSchemaField) != null && newFieldMapping.get(defaultSchemaField) != null &&
+                                    existingFieldMapping.get(defaultSchemaField).equals(newFieldMapping.get(defaultSchemaField))
                     ) || (
-                            e.get(defaultSchemaField) == null && newFieldMapping.get(defaultSchemaField) == null
+                            existingFieldMapping.get(defaultSchemaField) == null && newFieldMapping.get(defaultSchemaField) == null
                     )) {
-                        foundFieldMappingDoc = Optional.of(e);
+                        foundFieldMappingDoc = Optional.of(existingFieldMapping);
+                    }
+                    // Grabs the right side of the ID with "|" as the delimiter if present representing the ecs field from predefined mappings
+                    // Additional check to see if raw field path + log type combination is already in existingFieldMappings so a new one is not indexed
+                } else {
+                    String id = existingFieldMapping.getId();
+                    int indexOfPipe = id.indexOf("|");
+                    if (indexOfPipe != -1) {
+                        String ecsIdField = id.substring(indexOfPipe + 1);
+                        if (ecsIdField.equals(newFieldMapping.getRawField()) && existingFieldMapping.getLogTypes().containsAll(newFieldMapping.getLogTypes())) {
+                            foundFieldMappingDoc = Optional.of(existingFieldMapping);
+                        }
                     }
-                    // Additional check to see if raw field path + log type combination is already in existingFieldMappings so a new one is not inserted
-                } else if (e.getId().contains(newFieldMapping.getRawField()) && e.getLogTypes().containsAll(newFieldMapping.getLogTypes())) {
-                    foundFieldMappingDoc = Optional.of(e);
                 }
             }
             if (foundFieldMappingDoc.isEmpty()) {