Phone rings a couple of times and then cuts off

[JuliaMama]

My phone rings a couple of times and then cuts off, however it is not actually  ringing, so I am unaware.  

People say it is a bit disconcerting as it appears I am busy and am physically cutting them off, but it does not ring on my phone.

I don't know whether it is my old iphone 4, because it also does not alert me when I get messages and whats app, even though I put the alert button on.

It is very puzzling.

[kids]

Also check : Settings > sounds > Ringer and alerts and make sure the slider it fully to the right of the screen.

Then scroll down to Sounds and vibrations and make sure you have selected a ring tone and it is not on silent.

[JuliaMama]

I will have to find out from my friends and family if it is still ringing and cutting off now I have reset.  I will come back to you if it is still a problem - you seem to have a vast knowledge.  Thanks

[BandOfBrothers]

Do you have a half moon symbol in your iPhones status bar ?

The Do Not Dusturb setting.

https://support.apple.com/en-gb/HT204321