diff --git a/app/controllers/announcements_controller.rb b/app/controllers/announcements_controller.rb
index 4d06053..eb5c241 100644
--- a/app/controllers/announcements_controller.rb
+++ b/app/controllers/announcements_controller.rb
@@ -637,7 +637,7 @@ class AnnouncementsController < ApplicationController
         anns = top_anns + rest_anns
       end
     end
-    anns.each{|a| a["postdate"] = a["postdate"].in_time_zone(Time.zone.utc_offset / 3600).strftime('%Y-%m-%d %H:%M') rescue nil }
+    anns.each{|a| a["postdate"] = a["postdate"].in_time_zone(Time.zone.utc_offset / 3600).strftime('%Y-%m-%d %H:%M') if a["postdate"] }
     anns
   end
 
@@ -814,7 +814,7 @@ class AnnouncementsController < ApplicationController
         "title" => announcement.title,
         "subtitle_ann" => subtitle_ann,
         "update_user" => update_user,
-        "updated_at" => (announcement.postdate.in_time_zone(Time.zone.utc_offset / 3600).strftime('%Y-%m-%d %H:%M') rescue ""),
+        "updated_at" => (announcement.postdate ? announcement.postdate.in_time_zone(Time.zone.utc_offset / 3600).strftime('%Y-%m-%d %H:%M') : ""),
         "body" =>announcement.text,
         "image" => announcement.image.url,
         "img_src" => img_src,
@@ -878,7 +878,7 @@ class AnnouncementsController < ApplicationController
 
     OrbitHelper.render_meta_tags([{"property" => "og:title", "content" => announcement["title_translations"][locale]},{"property" => "og:site_name", "content" => Site.first.title},{"property" => "og:url", "content" => request.original_url.split("?").first},{"property" => "og:description", "content" => meta_desc},{"property" => "og:image", "content" => announcement["image"]["original"]},{"property" => "og:type", "content" => "Article"}])
 
-    datetime = DateTime.parse(announcement["postdate"])
+    datetime = announcement["postdate"] ? DateTime.parse(announcement["postdate"]) : nil
 
     bulletin_carousel_images = Array(announcement["bulletin_carousel_images"])
     resume_btn_title = (I18n.locale.to_s =="zh_tw") ? "繼續播放" : "resume"
diff --git a/app/helpers/announcements_helper.rb b/app/helpers/announcements_helper.rb
index 3002ced..f0fa4b6 100644
--- a/app/helpers/announcements_helper.rb
+++ b/app/helpers/announcements_helper.rb
@@ -146,12 +146,14 @@ module AnnouncementsHelper
           end
           flag = title.include?(keywords.to_s)
         end
-        if sflag && !eflag
-          flag = flag && (anns.postdate<=etime)
-        elsif !sflag && eflag
-          flag = flag && (anns.postdate>=stime)
-        elsif !sflag && !eflag
-          flag = flag && (anns.postdate>=stime) && (anns.postdate<=etime)
+        if anns.postdate
+          if sflag && !eflag
+            flag = flag && (anns.postdate<=etime)
+          elsif !sflag && eflag
+            flag = flag && (anns.postdate>=stime)
+          elsif !sflag && !eflag
+            flag = flag && (anns.postdate>=stime) && (anns.postdate<=etime)
+          end
         end
         flag
       }