Where is the self-register for TCR in the admin portal?

@Jennifer Brown Thanks for your question!
It's not yet been implemented, but we're close.
We have to roll it out to our customers and I'm expecting the feature to be accessible early next week.
Thanks for your patience as we are working hard behind the scenes to put everything into place.

Hi @Jennifer Brown, the Service Web registration is now available. You may check the KB article below!
https://support.ringcentral.com/article-v2/Setting-up-TCR-registration-assigning-numbers-to-SMS-campaigns.html?brand=RingCentral&product=MVP&language=en_US