fix error

app/models/archive_file.rb

@@ -15,7 +15,12 @@ class ArchiveFile
   # BelongsToCategory =  :archive_file_category
 
   # PAYMENT_TYPES = @site_valid_locales
-
+  before_save do
+    cat = self.category rescue nil
+    if cat && ArchiveCategory.where(:category_id => cat.id).count==0
+      ArchiveCategory.create(category_id: cat.id.to_s)
+    end
+  end
 
   field :title, as: :slug_title, localize: true
   field :description, localize: true