diff --git a/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java b/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
index 1aa9697..49e1262 100644
--- a/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
+++ b/src/main/java/com/flowingcode/vaadin/jsonmigration/JsonMigrationHelper25.java
@@ -114,7 +114,7 @@ private static BaseJsonNode convertToJsonNode(JsonValue jsonValue) {
         JsonArray jsonArray = (JsonArray) jsonValue;
         ArrayNode arrayNode = nodeFactory.arrayNode(jsonArray.length());
         for (int i = 0; i < jsonArray.length(); i++) {
-          arrayNode.set(i, convertToJsonNode(jsonArray.get(i)));
+          arrayNode.add(convertToJsonNode(jsonArray.get(i)));
         }
         return arrayNode;