I've seen this before with Hubspot.
You probably just need to find the ID of your workspace for LeadConnector and then you have to get out of this view in Zapier so you can enter it in manually - but to do that you have to get out of this view and shift to the other mode (I think there's an option for that just to the right of what you captured in your screenshot) - then you plug in your ID, and it may work from there