Ah, make sense, that's a common pitfall. Thanks for coming back to post your solution!
Also, this endpoint is currently deprecated, but will continue to be supported in its current form for a while. I don't have any definite timeframe for when it will be fully sunset, but we'll communicate the change on the Developer Changelog before we do: https://developers.hubspot.com/changelog
Can you give me the raw response you get from HubSpot? I'm able to see the associated contact vids when making that same request to your portal, so I'm not quite sure what's going on.
Also, quick side note: While that endpoint technically still works, it's been deprecated in favor of the more robust Associations API. I'm happy to help figure out what's going on with the endpoint you're using, but I'd also recommend switching to the Associations API whenever possible.
Ah, make sense, that's a common pitfall. Thanks for coming back to post your solution!
Also, this endpoint is currently deprecated, but will continue to be supported in its current form for a while. I don't have any definite timeframe for when it will be fully sunset, but we'll communicate the change on the Developer Changelog before we do: https://developers.hubspot.com/changelog