At this time, you are not able to change the email address associated with your DrChrono account on your own.
Please contact your account manager, use our chat support, or submit a support ticket here.
For security purposes, please make sure to send the email from the actual address that is already associated with your DrChrono account (i.e. the one that you want to change from) and make sure to include the new address that you want to be updated.