How To Change MCN iPhone To set MCN on iPhone Dial **5005*7672*+6797000037#SEND Android Launch SMS Applciation. Tap on Menu and go to settings. Scroll down and select Message/Service Center Number. Set it to +6797000037 and Tap on OK. Related articles Information on why you get a sim error message and how to fix it How do I activate my new SIM card? How do I activate my new SIM card?