Update request gets error "cannot be set. It is not on the appropriate screen"

[johndlawlor]

I'm trying to update a field in a issue using the following Python code:

jira_server = "http://servername"
jira_password = "xxx
jira_user = getpass.getuser()
jira_server = {'server': jira_server}
jira = JIRA(options=jira_server, basic_auth=(jira_user, jira_password))
jira_issue = jira.issue(ticketId)
jira_issue.update(fields={jira_issue.fields.customfield_11111:'value'})

I then get the error: 

JiraError HTTP 400 url: http://server/rest/api/2/issue/123456

"cannot be set. It is not on the appropriate screen, or unknown."

If I log into Jira as the same user i can edit this field

Thanks.