How are you setting the URL? When I include quotes around the item in the CSV file, it resolves as a string with pm.iterationData.get('companies'). It looks like the error you’re getting is coming from the URL containing quotes. I’m wondering if those quotes are sneaking in via some other way. If I include {{companies}} as a variable in the URL, that’s also resolving correctly. Are you using that variable syntax in the URL address bar or are you setting the URL in a pre-request script via pm.request.url?
Best,
Kevin