Are you trying to connect Microsoft Teams with with Jira Cloud or a Jira Server instance?
In Teams, there are two different connectors available:
If you are want to connect a Jira Cloud instance, it would be the Jira Cloud connector that you need. For me, that one doesn't ask for a Jira ID. Rather it gives a Webhook URL and instructions on how to add that into your Jira Cloud site (admin permissions required)
Based on the docs here - https://www.msteams-atlassian.com/JiraServer/ - Jira ID is for the Jira Server version of the app/connector so would not be relevant if you are working with Jira Cloud.
Here's what it says about Jira ID, just in case you are on Server though:
Jira ID is a unique identifier that is generated after Jira app (add-on) installation. If Microsoft Teams for Jira app (add-on) is installed in your Jira and you have the administrator permissions, you can see the Jira ID at the bottom of the configuration page in Jira. In case you don’t have administrator permissions, please contact your Jira administrator to provide you with the Jira ID from the add-on configuration page."
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