To add another team member to a file, follow the steps below:
1. open the context menu of the file
Navigate to the list of files. Select the "Edit file" option in the context menu
2. click on the "Add team member" button
The sidebar of the file will now open. Under the "Team" section, you will find the team members who are assigned to the file. On the right you will find the "+Add team member" button. Click on the button to open a pop-up.
3. select the desired team member
You can now select the desired team member to be added to the file team. The new team member is added to the file as an assistant.