If I transferred from ATD 2020 to ATD 2021 and cannot attend the new dates, how do I change my registration? Natasha Porter Updated September 28, 2020 19:29 Follow Please contact ATD Customer Care for assistance. Email email@example.com or call +1 703.683.8100 or 800.628.2783. Related articles If I have to cancel my ATD 2021 conference registration after it has been transferred, what is the policy? If I am transferring to ATD 2021, how will I receive confirmation of my registration? Is ATD offering in-person courses? When can I learn more information about ATD 2021? How do I tag or contact ATD on social media?