Hi @vero1238
You need to check if your Google Developers Console is enabled
1. Go into your domain administration @ https://admin.google.com/AdminHome
2. Go to Apps
3. Go to Additional Google Services
4. Find the Google Developers Console and check if is it enabled. If isn’t you need to enabled doing click on it and then pressing the button enable.
Additional to this you need to check if your Google Calendar is enabled. To check this you need to:
1. Go into your domain administration @ https://admin.google.com/AdminHome
2. Go to Apps
3. Go to G Suite
4. Find the Google Calendar service and check if is it enabled. If isn’t you need to enabled doing click on it and then pressing the button enable.
For your API Key:
1. Log in to your Google Cloud Platform API & Services
2. Click on your API Key
3. In Restrictions Area put your website like this yourname.com/* or put the restriction to none.
That’s how I solved the problem and you don’t need to buy the addon, for me this free plugin is working pretty well ??