A Decennial user can be identified by their email address ending in @2020census.gov AND by confirming they are a DAPPS employee (vs. NFC Employee). Their employee type MUST be confirmed before using a Decennial SR.

I apologize that I have been unable to locate an account for you. As you confirmed that you are a DAPPS employee the DOC Census Administrators have advised you would need to reach out to the Decennial Service Center at 855-236-2020 and choose option 9.