diff --git a/api/src/main/java/org/cardanofoundation/rosetta/api/construction/service/CardanoConstructionServiceImpl.java b/api/src/main/java/org/cardanofoundation/rosetta/api/construction/service/CardanoConstructionServiceImpl.java
index 651f394b..f1a18dd0 100644
--- a/api/src/main/java/org/cardanofoundation/rosetta/api/construction/service/CardanoConstructionServiceImpl.java
+++ b/api/src/main/java/org/cardanofoundation/rosetta/api/construction/service/CardanoConstructionServiceImpl.java
@@ -503,7 +503,8 @@ public String extractTransactionIfNeeded(String txWithExtraData) {
     byte[] bytes = HexUtil.decodeHexString(txWithExtraData);
     Array deserialize = (Array) CborSerializationUtil.deserialize(bytes);
     // Unpack transaction if needed
-    if (deserialize.getDataItems().size() == 1) {
+    if (deserialize.getDataItems().size() == 1 && deserialize.getDataItems().getFirst().getMajorType()
+        .equals(MajorType.ARRAY)) {
       deserialize = (Array) deserialize.getDataItems().getFirst();
     }
     if (deserialize.getDataItems().isEmpty()) {