If a phone says the person you have called is unavailable

[Phone700]

Rung a mobile phone it rung once and then said the person you have called is unavailable. Is this an out of service phone or one that's off?

Usually one that's off (that's the message DH always gets when he phones FIL's mobile).

Or - you can reject calls on some phones with that message.

Happens when they've no signal - e.g. on a train or underground somewhere.

People are telling me out of service but surely they don't ring at all?

Remember the ring you hear on your handset when making a call is not actually the other phone really ringing. Hence you may hear one ring before you get that message.

What do phones do when they are out of service then?

It might be the person rejecting your call. I do that sometimes if I'm busy and don't have time to take the phone.

I've text and didnt get a message saying my text couldn't be delivered so assuming it's not out of service

The only time I've had a message a text couldn't be delivered when when I was sending and had no network connection.

So it's likely the phone is still in service?

I would say so, yes - what's going on and why are you asking?

It's a friend who I'm concerned about.

If the person doesn’t have voicemail set up then you get the unavailable message.
Does your friend have an iPhone? Ringing once and then the message is a tell tale sign of being blocked, you wouldn’t get a message to say a text wasn’t delivered either.

No they don't have an iPhone

Can you call round or is there anyone near your friend who can check on them? You can always call the non-emergency police number and ask them to do a welfare check if you think something is seriously wrong.

If it rings once then goes to voicemail I think it means your number has either been blocked or they’re rejecting the call as soon as it comes through?

By voicemail I mean the unavailable message.