Voicemail yet no missed call

[#1]

Hi all

Can anyone help me with this scenario please? It has happened several times, most recently yesterday.

I had an alert from my voicemail around 5.30 pm and when I listened to the message, it was an urgent message from a sick friend that had been left an hour or more earlier.

Why did I not get a missed call?

Actually I don't believe the phone ever rang as I was indoors all afternoon and my phone was to hand at all times.

So why did it go straight to voicemail?

Why did the alert take so long to come through?

The Samsung phone is totally up to date with software, there are no flatspots in my house and I need to have a reliable connection especially at the moment. Can anyone advise?

Thanks

[#2]

Mostly likely network coverage or some issue that meant your phone wasn't actually registered on the network when the call came in, hence it went to voicemail.  The fact that it took a while for the voicemail to be delivered is also a bit suspicious, suggesting your phone wasn't registered for a long time when you thought it was.  I've had issues like that with all the networks over the years, and just accepted they aren't 100% reliable all the time (this is radio based technology after all, and isn't designed for critical usage)

If comms are really important it might be worth installing a messaging app such as WhatsApp connected via  home Wifi and get people to use that - at least with WhatsApp people know when messages have been delivered etc.