Block unwanted phone numbers calling u on AT&T cell phone

How to block phone numbers on AT&T cell phone.
A visitor ask me this question via email:

Question:
from Marshal (by mail):My boss is havingAT&T Motorola mobile phone whenever he is in meeting he is getting unwanted calls on his number he is very irritated with this issue. I want to know is there any way where my Boss can block a number from calling to his cell number. If yes can you tell me whats steps my boss need to follow to activate it.

Answer:
Dear marshal,here is the sol,that your Boss can follow. 

1.AT&T provide such kind of service fro which you need to first
2.Call on 611 from your phone. Tell your customer service you'd like to add Smart Limits" to you phone plan.
3.Then they will ask you to give the numbers give them up to 15 numbers you would like to block from calling you. 
4.Now go online to your account to add any more numbers or to take numbers off of your blocked list.
5.Thats it,are you satisfied?
Ok.
Hav a nice blocking..

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