I'm having the same problem here. We have 2 environments (UAT and PROD), and both is doesn't work the mail trigger too. 

Triggers do not persist after machine restart(Automation Anywhere 360).

Most probable reason: Control room upgrade> bot agent updated automatically> device restarted automatically

Solution: Login to bot runner machine> Login to bot AA control room with bot runner account > Wait for Trigger successful message.

This would reinstall the trigger and start working after few minutes.

Yep, but even logging into the CR with the user for which the trigger is configured from within the correct runner and the message "trigger configuration successfuly started" appears, the trigger does not start the process anymore

To solve the problem with the input fields, I opened the task packages and changed to the last recorder package avaliable (changed from 2.7.3 to 2.8.6) and it's working now.

I tried to do the same with the e-mail trigger package but keeps not starting the taskbot when a new e-mail is received

After getting support from Automation Anywhere, we discovered that the e-mail connection by e-mail server action is not working anymore with the because of a microsoft update where is not possible to use basic authentication anymore. (https://apeople.automationanywhere.com/s/article/Basic-Authentication-deprecation-in-Microsoft-Exchange-online)

As workaround we can use the "Outlook" connection type to read e-mails.

The e-mail account should be configured in outlook app in the machine and the programmatic access option should be configured as "Never warn me about suspicious activity (not recommended)", this way automation anywhere can read the e-mails without the prompt appearing.