Hi Gabrielle,
You have to put your API Key. You can find it in your Developer Dashboard. You can create a app for that relevant API and go to that App’s security section and a API Key will created for you and you can also create more API Key’s inside that too. API Keys / Key Rotation
Like this : For me it doesn’t works because I didn’t subscribed to this API Key. For you it will work because you have subscribed!
Hope I’m correct 
Thank you