It's doing this on my Galaxy S9 on Optus, and I've checked ALL the settings however random calls, especially from "Private Number" (which is the emergency phone at work) have gone straight to voicemail. I've rung the phone myself from my second mobile phone, and it's worked normally, but it's concerning that emergency calls can't get through with no warning or indication on the phone itself.
Hi @OrangeIke, sorry to hear about your incoming call issue. It is very strange that only certain calls are diverting straight to voicemail and not ringing at all. We cannot divert specific number only. If diversions (busy, no answer or unreachable) are set only then the calls will divert and this would apply to all incoming calls. Can you make sure you have not tuned ON the "blocked anonymous calls" feature on your Samsung phone. You can check this by navigating into → From the Home screen, tap the Phone icon > Tap MORE > Tap Settings > Tap Call blocking > Make sure the Block anonymous calls is not ON.
I went through all the settings when it happened - there was no divert on. I wonder if there had been a transient drop-out in service as it happened again today in my office and I noted that all the bars of service had disappeared at the same time. Normally, those locations have 4G capability but there was no VoLTE or 4G indicator on the phone when it did it today, and no bars of service. My iPhone which was sitting next to my Samsung was unaffected (it's connected to a different network provider).
Don't think that Telstra will offer anything better. My iphone, with Telstra does exactly the same as this discussion says.
I've checked all the settings, and still nothing. The only thing I can think of is that the signal is low (one bar), and the SE iphone doesn't like it.
It happens with messages too, of course, which is very annoying with govt websites that send codes. They come in hours later, or not at all.
I'm getting this too on my YES Optus android phone. And not just from privite numbers. It makes things hard when you're expecting calls and it doesn't ring. I've had to rescedule twice now because the call went straight to voicemail. And the phone was in my hand! I did the ##21# thing yesterday to see if that helps. But we'll see.