Mobile phone can't send short messages, error code 28.

Enter the dial key to open the dial interface, and press enter? * # * # 6 130 # * *, and set it in the pop-up page to restore the SMS function.

Detailed steps:

Take the Android phone as an example:

1. Open the dialing interface and enter? *#*#6 130#*#*? .

2. Enter the mobile phone test status interface. Select the first item "Mobile Phone Information", and the dual-card selection interface will appear. Select an account that can't send SMS.

3. When the mobile phone information appears, drop it down and the GSM anto (PRL) interface appears.

4. In the interface, click "Need to open IMS registration", and it will become "Need to close IMS registration". Click the third item "Enable SMS via IMS", and then click "Disable SMS via IMS" to turn on SMS sending. Can be solved.

References:

Baidu Encyclopedia-SMS