I can't deactivate two-factor authentication

Hi! 

I’m trying to access my free docusign account. I’m blocked at the 2-factor authentication step as the phone number isn’t correct. I called the assistance and they managed to deactivate it for me to access. but the moment i try to go the privacy settings to change the phone number for the 2-factor authentication I’m asked to sign in again and blocked again with the 2-factor authent. 

Do you know what i can do to fix this?