Do I need to set the SMS center number for my IPHONE? Dongguan Unicom's mobile phone

The steps to set the number of the IPHONE SMS center are as follows:

Inquiry method on IPHONE: dial *#5005*7672# with iPhone.

Setting method: dial * 5005 * 7672 *+86 "SIM card home SMS center number" with iPhone #

Delete method: dial ##5005*7672# with iPhone.

Note: The set SMS center number is generally similar to the mobile phone number after +86. When setting the number of the SMS center, please insert and unplug the SIM card again. It is suggested to delete the SMS center number before resetting it, that's all.