diff --git a/lib/src/services/api_service.dart b/lib/src/services/api_service.dart
index 1a5e7701..7ba30aa1 100644
--- a/lib/src/services/api_service.dart
+++ b/lib/src/services/api_service.dart
@@ -236,28 +236,24 @@ class ApiService with JsonRPCUtil {
 
   /// Query the network to find a transaction from a list of addresses
   Future<Map<String, String>> getTransactionContent(
-    Map<String, String> addresses,
+    List<String> addresses,
   ) async {
     if (addresses.isEmpty) {
       return {};
     }
 
     try {
-      final transactionChainMap = await getTransactionChain(
+      final transactionChainMap = await getTransaction(
         addresses,
         request: 'data { content }',
       );
 
       final contentMap = <String, String>{};
 
-      transactionChainMap.forEach((key, value) {
-        final transactionList = transactionChainMap[key];
-        if (transactionList != null) {
-          for (final element in transactionList) {
-            if (element.data != null && element.data!.content != null) {
-              contentMap[key] = element.data!.content!;
-            }
-          }
+      transactionChainMap.forEach((key, transaction) {
+        final content = transaction.data?.content;
+        if (content != null) {
+          contentMap[key] = content;
         }
       });
 
diff --git a/test/api_test.dart b/test/api_test.dart
index 03f259ff..85680f91 100644
--- a/test/api_test.dart
+++ b/test/api_test.dart
@@ -70,10 +70,11 @@ void main() {
 
       test('getTransactionContent', () async {
         final contentMap = await ApiService('https://testnet.archethic.net')
-            .getTransactionContent({
-          '0000C85F189C13846ED91FFE30B08EF3B0E009780DAEEF4581F8B3D717D99CC954C0':
-              '',
-        });
+            .getTransactionContent(
+          [
+            '0000C85F189C13846ED91FFE30B08EF3B0E009780DAEEF4581F8B3D717D99CC954C0',
+          ],
+        );
 
         expect(
           contentMap[
diff --git a/test/transaction_test.dart b/test/transaction_test.dart
index 1f03d43e..899776e2 100644
--- a/test/transaction_test.dart
+++ b/test/transaction_test.dart
@@ -754,7 +754,7 @@ condition inherit: [
 
         const text = 'Hello👋';
         final tx = Transaction(type: 'transfer', data: Transaction.initData())
-            .setContent(uint8ListToHex(Uint8List.fromList(text.codeUnits)))
+            .setContent(uint8ListToHex(utf8.encode(text)))
             .addUCOTransfer(
               '0000b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646',
               toBigInt(0.00000001),
@@ -785,11 +785,11 @@ condition inherit: [
         await completer.future;
 
         final txAddress = tx.address!.address!;
-        final content = await apiService.getTransactionContent({
-          txAddress: '',
-        });
+        final content = await apiService.getTransactionContent(
+          [txAddress],
+        );
 
-        final decodedContent = String.fromCharCodes(
+        final decodedContent = utf8.decode(
           hexToUint8List(
             content[txAddress]!,
           ),