12306 is there a charge for SMS authentication? What if I can't receive the SMS verification code?

The short message fee is generally 0. 1 yuan/article. In general, as long as the passenger sends 999 to 12306, the passenger will reply and send the verification code in about 5 seconds. "When the passengers of mobile phone authentication are centralized, there may be network delay, which makes it impossible to reply the verification code quickly." If the SMS cannot be verified normally after being sent n times, you can directly call the customer service phone number 12306 to inform the customer service staff of the mobile phone number, and the customer service staff will inform the verification code to help passengers complete the mobile phone verification.