does not show the cronjobs

After registering the cronjobs, it shows that it was registered successfully. but then disappears from the screen and I can not edit or delete it.
as if he had not been registered

Did you have the latest version?

1.8 bulid 2

what is the cron job that you are trying to add?

0,15,30,45 <— mautic:segments:update
5,20,35,50 <— mautic:campaigns:update
10,25,40,55 <— mautic:campaigns:trigger

Your cronjob syntax is wrong, you need to fix that up. Then we will see in our end