Starting June 20, 2020, Amazon Pinpoint customers who send SMS with an alphanumeric sender ID to Indian recipients must register their use case. The Telecom Regulatory Authority of India recently updated the regulations on commercial SMS sending. Senders who have a local presence in India are required to register their use cases through the Distributed Ledger Technology (DLT) system. When you successfully register your use case, you can use an alphabetic sender ID to deliver your transactional messages or numeric sender ID to deliver your promotional messages to recipients who have Indian phone numbers. Messages that you send using a registered sender ID are billed at the standard rates. For current message sending rates, see the Amazon Pinpoint Pricing page.
Source:: Amazon AWS