Update profile picture
Make sure that the profile picture is set to be "Visible to anyone"
If the picture is visible to the organization only, re-upload the picture from the Google Profile page to make it publicly visible.
Once your team has set profile pictures and you have made sure they are publicly visible, please ask them to sign out and sign in again from TasksBoard.
Please note that changes made on the Google Admin page and new profile pictures can take up to 24h to take effect.