How does DocuSign SMS authentication work?
Overview. With Phone Authentication, a recipient requests a one-time passcode (OTP) to be delivered to their phone number, either by SMS or phone call. The recipient receives the code and then enters that code on their screen.
How do I enable SMS in DocuSign?
To enable SMS delivery in your developer account, open a support case with DocuSign Support if you have a production account. If you don't have one, visit the DocuSign Support page, select DocuSign API Integration Support under More Support Options, and submit details using the form.