How to Block Specific Calls on Your Cell Phone
Blocking numbers on your cell phone can be somewhat tricky. Some cell phone service providers have an option to block specific numbers but other carriers do not. If your carrier does not offer the ability to block incoming calls from certain numbers, then you can save the number as a contact and assign a silent ring tone to it. Although the calls will still come in, you won't hear them.
Visit your cell phone carrier's website and log in to your account.
Go to "My Services," click "My Cell Phone" and "Safeguards," and select "Spam Control."
Enter up to six or 12 numbers, depending upon your location, which you would like to have blocked. These numbers will no longer be able to contact you.