Blocking Users from Other Companies
You cannot delete or suspend users who are not part of your company and have shared some content with the users from your company. However, you can block these users.
Select the icon next to your name at the top.
Select Settings, then select the Users tab.
Select the Other Companies tab.
A list of all the users who are not part of your company is displayed.Select the icon next the user account that you want to block.
Select Block.
The selected user account is blocked. This user cannot view or access any shared document or folders from your company.