This article explains how to turn off automatic forwarding in Google Workspace. 

1. On your computer, open Gmail using the account you want to stop forwarding messages from.
2. In the top right, click Settings .
3. Click See All Settings.
4. Click the Forwarding and POP/IMAP tab.
5. In the “Forwarding” section, click Disable forwarding.
6. At the bottom, click Save Changes.