Not receiving calls from landline numbers

[Nadiaz]

I have used public mobile for more than a year now, but I still have problems receiving phone calls from landline numbers. From the cases I know, E.g. phone call from school office never reached me and I never get a missed call note. It didn't even direct them to the voicemail. Then I do get voicemail from my dentist but never received any missed call note either. 

Note: those numbers above are not on my block list, I can call them no problem. I think it s a landline problem as those are the ones I am aware of. I don't know if other office numbers tried to reach me and failed, as I would never have a way to get their feedback. 

I see lots of people have the same problem, but only happened when they transferred the number. Not sure what problem is mine, but def this is Not a one number issue. I have submitted a ticket and that agent told me to ask the numbers I missed to add #31# before my number to call (this is not something an office would do for me to test my number, they are not tech service.. ) and insisted there s nothing wrong with public mobile. I see no hope from the agent, so looking for some suggestions here.. 

Thanks in advance

[Nadiaz]

Thanks, it doesn't seem to be this problem either, as I got lots of spam calls and those numbers were not on my list either.. 

[Nadiaz]

Thanks for your reply. I forgot to mention, those two numbers I know are actually in my phone book, it was never blocked. Weird enough, I do get phone calls from "unknown" number .. it shows up with weird symbol but I do get them. And lots of spam calls. ..

[slusagm]

sound like you have the phone feature "Silent unknown caller" enabled.  With that, only number on your contact list will ring, the rest won't.  Check it

On iPhone , go to  Settings > Phone, then scroll down, tap Silence Unknown Callers, and turn off the feature

On Android, it could be called something else , but start with checking: Settings-> Block Number-> Block unknown/private numbers