Hi Steve, there's a new policy requiring mobile carriers' new registration to help verify messaging traffic from business phone numbers, which applies to all RingCentral customers. To know more about this, please see the article below.

https://support.ringcentral.com/article-v2/Intro-SMS-compliance-campaign-registration.html?brand=RC_US&product=RingCentral_MVP&language=en_US

You may also submit a Support Ticket if you need further assistance with registration. Go to https://support.ringcentral.com/new-case.html.