Find your List ID for ClickUp

You can see your ClickUp List ID in the URL when you are viewing the list in ClickUp.

​https://app.clickup.com/:workspace_id/v/li/:list_id

You may also try only the text within the inner hyphens:
9 - 123456 - 9
In this case, only: 123456

Also see:

https://help.clickup.com/hc/en-us/articles/6308896743575-Intro-to-List-Info