What is the reason for not receiving the message receipt after sending the message?

SMS receipt refers to the business that customers receive the receipt message immediately after sending the message with China Telecom's mobile phone. The contents of the receipt include the status information and additional information of whether the receiver successfully received it. The length of additional information is limited to 44 characters (including punctuation marks), and the content involves cultural entertainment, life health, practical knowledge, hot events and other fields.

After sending the SMS, you didn't receive the SMS receipt or it took a long time to receive the SMS receipt, which may be caused by the following circumstances:

1) SMS receipt is lost in network transmission, but this probability is very small.

2) System maintenance, which cannot be handled temporarily, can be resumed after the system is normal.

3) There is a delay in the network, and a receipt will be received later.

.4) Personalize and block certain types of receipts.

5) I chose lightning short message and changed my mobile phone, but the new mobile phone does not support lightning short message.

6) The message sent by the calling party to a special number will not receive an enhanced SMS call receipt. When the calling party sends a message by SMS or fetion (the number of the other party is prefixed, such as1065919110), the called party will reply directly, and the called party will not receive an enhanced SMS call receipt, but can only receive it by sending a point-to-point message.