If you have a case where you want to allow users to be able to impersonate other users and switch between their accounts then you will need to create a role to enable this type of access.
1. Navigate to Account settings then Roles from the left menu.
2. Create a new role
3. Enter a name for your role
3. Under "Access type" select "Impersonate other users with restrictions based on each users access"
4. Save the new role.
Now you can assign this role to new users that you want to allow to impersonate other users. You can find out how to do this from the article -