Configure the Webhook by entering the Webhook URL and Client token and save changes. Get the values from Chat24Plus > Settings > Business Messages > Synchronization.
Click Service account from the left menu and create a new key. Download the key and open it with a text editor (like Notepad). Copy the private_key and client_email, and paste the values in Chat24Plus > Settings > Business Messages > Synchronization.
You are done! To test your agent, visit https://business-communications.cloud.google.com/console/, click your brand to enter your brand's Overview area. Under Agent information > Agent test URLs, click on the button suitable for your mobile device and open the link from your mobile device.