Issue with HubSpot Update for LinkedIn Lead: Property values were not valid

I'm facing a strange issue. I have a relatively simple table that enriches some leads from LinkedIn and then updates the contact record in HubSpot. It works great for about 100 records, but for one contact I'm getting an Error on the HubSpot update. The error is "Property values were not valid". The update is configured to send about 10 variables to HubSpot. I've tried removing each of them one at a time to identify which one is not valid, but continue to get the same message for this one record. I've looked at each of the fields (name, url, etc.) and they all look clean for this row. Are there logs somewhere that would indicate what property is not valid? The generic failure to update the HS record is really frustrating. TIA for any help you can provide.