I want to add a rule that automates sending an email when ever a task is moved from 'progress' to 'to do'. I would like to link this with atlas CRM so when ever you choose a contact person and company it automatically sends a mail to them. This is how the CRM in connected to the task:

Now the question is how do I send an email to the contact in the issue? I have the automation rule set up like this for now:

I already got an error running this, so I know that {{issue.Contact}} is not correct. But maybe a better question is: how do I use smart values. I feel like there is not a lot of documentation on this to explore the topic. So how would I make sure the mail is send to the correct contact added to the task or/and how do these smart values work in general? Can they also use something from a third party like CRM?