How do I turn on alerts for a missed call when the phone is off?

[LoveLia]

Hi, I just got a new iPhone and now I can’t get text alerts when I miss a call when the phone is off, I tried my old sim in the 3 phones I have and the old sim received a message for each phone so I know it’s not the phone that’s the problem. Does anyone know how I can turn these alerts back on for this sim too? Thank you! 

[Geluk]

Perhaps if you told us which i phone others may help, or try asking on an Apple forum!

[LoveLia]

Sorry I didn’t think that mattered, it 14 plus. I already looked on Apple and it’s an not to do with the phone apparently it’s the service provider  

[JonathanB]

Hi @LoveLia,

If you dial your Voicemail on 123, then once you reach the main menu after any new messages play, it should be option 5 for missed call alerts.

Hope this helps!
Jonathan