Steps to reproduce:
Clone existing "Jira Service Management" Media Type.

Set up new media type with a values

jira_url = 
jira_user = 
service_desk_id = 
jira_request_type_id = 
jira_password =

Enable media type under Alerts-> Media types and test media type by clicking "Test" button:
To be able to test set required values values

alert_message = Test alert message
alert_subject = Test alert message subject
event_source = 0
event_value = 1 
event_update_status = 0

I got warning errors:

00:00:00.001 [Warning] [Jira Service Management Webhook] No event tags were found. Should be an object. Received event tags: "{EVENT.TAGSJSON}".
00:00:00.001 [Warning] [Jira Service Management Webhook] No customfields found.

*Issue #1 * For some reason media type does not work when no custom fields are defined in media type and event tags not defined.

added custom field aned event tags json

customfield_10034 = zabbix
event_tags_json = [{"tag": "test_tag","value": "test"}]

and repeat test

Result

I get error response "Key format is not valid"

912037:20260730:100051.579 [Jira Service Management Webhook] Response has been received: {"message":"Key format is not valid!","took":0.001,"requestId":"0ed54438-7b7d-4005-aaf3-e51f8ed22068"}

Expected:
Jira issue is created.