We had identified outbound SMS failure from sub-accounts due to technical issues. We have resolved the issue.
Start Date and Time: 27-Aug-2018 00:00 PDT End Date and Time: 27-Aug-2018 04:00 PDT
Affected Service: Outbound SMS
If you have any questions, please feel free to reach out to our support team. Please click on the following link to submit a support ticket: https://support.plivo.com/support/tickets/new