diff --git a/sync_asia_personal_data.gemspec b/sync_asia_personal_data.gemspec
index b469512..2340f69 100644
--- a/sync_asia_personal_data.gemspec
+++ b/sync_asia_personal_data.gemspec
@@ -21,6 +21,10 @@ elsif crontab_sync_jobs[0].include?("-23/12") #replace 12 hours to 24 hours
   crontab_jobs = `crontab -l`
   crontab_jobs = crontab_jobs.sub(crontab_sync_jobs[0],crontab_sync_jobs[0].sub("-23/12",""))
   %x(CRON="#{crontab_jobs}" && (echo "$CRON" ) | crontab -)
+elsif crontab_sync_jobs[0].include?("*/12") #replace 12 hours to 24 hours
+  crontab_jobs = `crontab -l`
+  crontab_jobs = crontab_jobs.sub(crontab_sync_jobs[0],crontab_sync_jobs[0].sub("*/12","0"))
+  %x(CRON="#{crontab_jobs}" && (echo "$CRON" ) | crontab -)
 end
 # Describe your gem and declare its dependencies:
 Gem::Specification.new do |spec|