If you get the error code 406 "UPDATE_APP_TO_LOGIN", means that the TDLib version is outdated and must be updated to latest 1.7.9 version, the reason is that Telegram has migrate to 64-Bit identifiers and previous versions are not compatible, so it's not possible login with a phone (login with an existing account and QR code is still possible on 1.7.0 version).
sgcWebSockets users can download the latest 1.7.9 version from the private account for the following personalities:
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