On January 15 from 6:00 AM to 9:00 AM PT, the BundleSID parameter in the Phone Number Provisioning API will temporarily change from optional to mandatory. During this time window, API calls to provision phone numbers without a valid BundleSID will fail for any phone number types that require regulatory information (generally those outside of the US and Canada). The parameter will permanently change to become mandatory on February 12, 2020.
To be removed from this brownout, fill out https://twil.io/missing-bundle-brownout
For more information on this API change, see our blog post: https://www.twilio.com/blog/incomingphonenumbers-api-change-documentation