diff --git a/tools/tu_config.py b/tools/tu_config.py
index 71f2c1b4..52cf00d4 100644
--- a/tools/tu_config.py
+++ b/tools/tu_config.py
@@ -231,6 +231,7 @@ def update_asset_slice_config(tu_name: str, binary_slice_file_path: str, asset_s
 
         binary_commented_map = data[binary_commented_map_key]
 
+        insert_tu_name_comment = True
         for section in symbols_for_tu[".data"].sections:
             for asset_symbol in section.symbols:
                 print("Add entry for: " + asset_symbol.symbol_name + "? (y/n)")
@@ -244,10 +245,14 @@ def update_asset_slice_config(tu_name: str, binary_slice_file_path: str, asset_s
                 asset_commented_map : CommentedMap = None
                 if binary_commented_map.__contains__(asset_symbol.symbol_name):
                     asset_commented_map = binary_commented_map[asset_symbol.symbol_name]
+                    insert_tu_name_comment = False
                 else:
                     asset_commented_map = CommentedMap()
                     binary_commented_map.insert(len(binary_commented_map), asset_symbol.symbol_name, asset_commented_map)
-                    binary_commented_map.ca.items[asset_symbol.symbol_name] = [None, asset_symbol.symbol_name, None, None]
+
+                    if insert_tu_name_comment:
+                        insert_tu_name_comment = False
+                        binary_commented_map.yaml_set_comment_before_after_key(key=asset_symbol.symbol_name, indent=2, before=tu_name)
 
                 # Add in the address range
                 address_commented_seq: CommentedSeq = None