diff --git a/fieldExtraction/src/hotfix_helper_funcs.py b/fieldExtraction/src/hotfix_helper_funcs.py
index 7d63fa7..a51384a 100644
--- a/fieldExtraction/src/hotfix_helper_funcs.py
+++ b/fieldExtraction/src/hotfix_helper_funcs.py
@@ -72,10 +72,10 @@ def clean_output_postprocess(merged_df):
     merged_df['dummy_other'] = merged_df['dummy_other'].apply(lambda lst: [x for x in [remove_alphabets(x) for x in lst] if x is not None])
     merged_df['dummy_other_signatory'] = merged_df['dummy_other_signatory'].apply(lambda lst: [x for x in [remove_alphabets(x) for x in lst] if x is not None])
     
-    merged_df['dummy'] = merged_df['dummy'].apply(lambda lst: [add_hyphen_if_needed(x) for x in lst])
-    merged_df['dummy_other'] = merged_df['dummy_other'].apply(lambda lst: [add_hyphen_if_needed(x) for x in lst])
-    merged_df['dummy_other_signatory'] = merged_df['dummy_other_signatory'].apply(lambda lst: [add_hyphen_if_needed(x) for x in lst])
-    
+    merged_df['dummy'] = merged_df['dummy'].apply(lambda lst: [x for x in [add_hyphen_if_needed(x) for x in lst] if x is not None])
+    merged_df['dummy_other'] = merged_df['dummy_other'].apply(lambda lst: [x for x in [add_hyphen_if_needed(x) for x in lst] if x is not None])
+    merged_df['dummy_other_signatory'] = merged_df['dummy_other_signatory'].apply(lambda lst: [x for x in [add_hyphen_if_needed(x) for x in lst] if x is not None])
+
     merged_df['dummy'] = merged_df['dummy'].apply(list_to_string)
     merged_df['dummy_other'] = merged_df['dummy_other'].apply(list_to_string)
     merged_df['dummy_other_signatory'] = merged_df['dummy_other_signatory'].apply(list_to_string)
diff --git a/fieldExtraction/src/utils.py b/fieldExtraction/src/utils.py
index e8e68c8..1d2777f 100644
--- a/fieldExtraction/src/utils.py
+++ b/fieldExtraction/src/utils.py
@@ -352,6 +352,6 @@ def add_hyphen_if_needed(input_str):
     
     # Ensure the output is in the format 'xx-xxxxxxx'
     if not bool(re.fullmatch(r"\b\d{2}-\d{7}\b", input_str)):
-        input_str = 'N/A'
+        input_str = None
 
     return input_str
\ No newline at end of file