They called everyday until I found this booklet online. I learned how to block 800 numbers and 866,877 numbers. When I asked AT&T to block them, they refused. Are they in cahoots with these debt collectors? After searching for several days I found a phone model that blocks toll free numbers and a phone service that has a dashboard to login and selectively block all the callers from the last 100 callers! Look for yourself.
http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Ddigital-text&field-keywords=how+to+block+a+phone+number
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