diff --git a/formity/scripts.py b/formity/scripts.py
index db127f6..6a0713a 100644
--- a/formity/scripts.py
+++ b/formity/scripts.py
@@ -59,7 +59,7 @@ def import_file(input_file, model, lookup, columns=None, delimiter=',', ignore_h
 def extract_postalcodes():
     for r in FaceshieldRequest.query.all():
         code = re.findall(r'(\d{2})\s*-\s*(\d{3})', str(r.entity_info))
-        if code:
+        if code and not r.shipping_postalcode:
             r.shipping_postalcode = '-'.join(code[0])
             r.shipping_city = PostalCode.query.get(r.shipping_postalcode).city
             print(r.id, r.shipping_postalcode)