not getting authentication option via SMS

Hi there!

I hope you are doing well.

The options that you are looking for are available only with business and enterprise-level service plans.

As you have a Creative Cloud All Apps subscription, it includes Adobe Sign individual plan.

To get those options available, you will need the business or enterprise-level service account.

For more information about the Adobe Sign plans, please refer to the following link: https://acrobat.adobe.com/us/en/sign/pricing/plans.html

To know more about the Two-step authentication feature, these help articles will help: 

https://helpx.adobe.com/sign/using/signer-identity-authentication-methods.html

https://helpx.adobe.com/sign/using/customize-sms-authentication.html

https://helpx.adobe.com/sign/using/enforced-identity-authentication.html

I hope this information helps.

Thanks,

Anand Sri.