How to, using automation, add and remove a request participant via email address

[Remy]

Basically I have an issue type that adds and removes request participants based on changes to an object field. In the object field the user's name and email is stored but not their customer accountID.

What I want to do is when the object field changes, remove the specific old RP and add a new one. I know how to do it with the account ID, but I am having trouble doing it when using just the email. At the moment I tried this in the "advanced" edit issue but it doesn't seem to work: 

{"update": {
"Request participants": [
{
"add": {"email":"{{issue."assigned contractor".email}}"}
},
{
"remove": {"email":"{{lookupObjects.email}}"}
}
]
}
}

 The lookupObjects looks up an asset in my db that contains name and email from the {{fieldchange.fromstring}}

Using the auditlog it seems like {{lookupObjects,email}} is returning empty...

[Bill Sheboy]

Hi @Remy -- Welcome to the Atlassian Community!

First thing, I am not using JSM and my suggestions are based on what I know about automation rules...

To add / remove users with JSON for Jira Cloud, the id value is needed, as described here:

• https://support.atlassian.com/cloud-automation/docs/advanced-field-editing-using-json/#Request-participants
• https://confluence.atlassian.com/jirakb/how-to-add-update-request-participants-using-automation-for-jira-1157468434.html

Please check if the accountId attribute is available in the lookup object.  If it is, try using that.

Kind regards,
Bill