diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -9,10 +9,10 @@
     def maximumNumber(self, num: str, change: List[int]) -> str:
         num = list(num)
         on = False 
-     for i, ch in enumerate(num): 
-         x = int(ch)
-         if x < change[x]: 
-              on = True
-              num[i] = str(change[x])
-         elif x > change[x] and on: break
-    return "".join(num)
+        for i, ch in enumerate(num): 
+            x = int(ch)
+            if x < change[x]: 
+                on = True
+                num[i] = str(change[x])
+            elif x > change[x] and on: break
+        return "".join(num)