Error in obtaining vertical and horizontal verification code.

The reason why the airline made an error in obtaining the verification code;

1. User's mobile phone number is blocked by the operator. Such notification messages were complained by operators as spam messages, which led to being blocked by operators.

2. Blacklist settings such as SMS security software. In the past, stricter interception rules were set in mobile phone short messages.

3, mobile phone internal browser privacy settings. The security level of the browser is too high or the setting to block "third-party Cookie and website data" is set.

The number of short messages sent exceeds the maximum limit of one day. In order to avoid short message bombing and waste of resources, some mobile phones set up a maximum of ten short messages per mobile phone number every day.

5. The signal network in the area where the mobile phone is located is not good, and the communication is delayed. Due to network or geographical problems, the authentication information sent by the server may be delayed.