Add back mismatched indices
diff --git a/manimlib/animation/transform_matching_parts.py b/manimlib/animation/transform_matching_parts.py
index e82bafafe8..ef62ff7d2a 100644
--- a/manimlib/animation/transform_matching_parts.py
+++ b/manimlib/animation/transform_matching_parts.py
@@ -192,6 +192,8 @@ def add_anims(anim_class, indices_lists_pairs):
                     target_indices_lists, target_indices
                 )
                 if not source_indices_lists or not target_indices_lists:
+                    source_indices.extend(it.chain(*source_indices_lists))
+                    target_indices.extend(it.chain(*target_indices_lists))
                     continue
                 anims.append(anim_class(
                     source.build_parts_from_indices_lists(source_indices_lists),

## Motivation
Fix a bug in `TransformMatchingStrings` class.

## Proposed changes
- M `manimlib/animation/transform_matching_parts.py`: Add back mismatched indices.
