Block unknown numbers from iphone4?

Some one keeps on stalking me and keeps calling me. I've contacted my server

company but they said they can't do it ( I'm on optus) theyve suggested I should change my number for $55 dollars but I don't
Want to, it's so expensive! I don't
Want to jailbreak my iPhone either. I know who they are but I've told them to stop but they still keep on calling me! I recognize her voice, she acts like she has an Indian accent but I know it's her but she won't admit it! Is there anyway to block these calls and texts from unknown numbers without jailbreaking
My phone? I've already told server company, but they don't provide
This service

Blocking a call is easy, what you need to do is-
Download Truecaller (an app on iPhone)
Open truecaller
go to call filter
click the plus sign
paste the number

  • When you Block Caller on iPhone, does it completely block them or do they show up as Unknown? I routinely "Block Caller" telemarketers, so does using the iPhone "Block Caller" option block all calls, or will the calls still come through and just show up as "Unknown"? I've received a lot of "Unknown" phone calls lately, so that's what I was attributing it to.
  • Unknown iPhone passcode set by unknown person? A passcode has been set on my iPhone without me knowing, now it is locked up. It says here to connect it to my computer and back up then restore my iPhone. Will this clear everything off my phone or will it be the same as it was before it got locked? I have only attempted unlocking it about 5 times in fear of disabling it. I do not want to back up then restore it if it will clear everything off and transfer it to the computer. Are there any alternatives to unlocking my iPhone?
  • Is it possible to block block numbers? I have a iPhone I just a call about an hour ago. It was from a blocked number they left a voice mail witch was only 3 seconds long. S/he didn't even say anything. I would love to know if I can block this. They are really scary for me.
  • IPhone app that blocks unknown numbers calling? What apps blocks unknown numbers on iPhones? I don't care if you have to pay I just want one that works well. I'm NOT going to jailbreak my phone for this either.