So, after a month and a half of mailing letters to ERC [Enhanced Recovery Co], with NO RESPONSE to my PFD letters, I somehow finally got a call yesterday on my cell phone from an ERC CSR. The girl on the phone (who was quite rude to say the least) gave me their usually debt collection spiel and ending by asking me how I was going to pay the $72 debt that I owed. I asked if the call was in response to my PFD letter, and she claimed that ERC received no letter from me as there are no notes on my account indicating a PFD was submitted by me. She even went as far as to say that the letter 'wouldn't do me any good anyway since ERC does not delete'. I find this odd that I haven't received a call from ERC in nearly 4 years only to get a call after I send a PFD. What can I do at this point? I am considering going straight to AT&T to settle, however, there's no guarantee that ERC will delete the TL. 
Does att still own your debt? There are a couple recent threads on dealing with erc and att.
I can tell you that I am still working on trying to get it deleted. My story in case it helps you:
Called att and asked them (over the phone) to pull the account back from erc and I would pay in full ($580!!). Got a verbal promise and so paid. Immediately called the office of the president and asked to verify my account was going to be deleted as promised. Put on hold and woman came back to say that it would not unless there was an error somehow on atts part.. And since there wasn't, then no. I was given misinformation and the account would just update to paid. Two days later erc updated to paid $0. I called erc and asked for it to be removed bc I never paid erc and actually had no communication with them at all. They said att would have to ask for deletion. Called att customer service and explained what I was promised and that it still hasn't happened. Woman asked me to three way erc and she would tell them to delete. Did that and both cust service reps were clueless as to what was going on. Hung up and called back att explained again and this time the woman said they forgot to take my account out of write up status and she did that for me so I should be set. This was two weeks ago and still no change. Called yesterday and spoke to collections dept at att. Woman said that they have done everything they can on their end that now erc has to choose to delete it. So... That's where I am. You may want to choose a different path.
If I could do it over again, i would call att eo with the mistake that they made (if they did in your case) and start from there. Get it in writing via chat, or something.
Good luck!!
I can tell you that I am still working on trying to get it deleted. My story in case it helps you:
Called att and asked them (over the phone) to pull the account back from erc and I would pay in full ($580!!). Got a verbal promise and so paid. Immediately called the office of the president and asked to verify my account was going to be deleted as promised. Put on hold and woman came back to say that it would not unless there was an error somehow on atts part.. And since there wasn't, then no. I was given misinformation and the account would just update to paid. Two days later erc updated to paid $0. I called erc and asked for it to be removed bc I never paid erc and actually had no communication with them at all. They said att would have to ask for deletion. Called att customer service and explained what I was promised and that it still hasn't happened. Woman asked me to three way erc and she would tell them to delete. Did that and both cust service reps were clueless as to what was going on. Hung up and called back att explained again and this time the woman said they forgot to take my account out of write up status and she did that for me so I should be set. This was two weeks ago and still no change. Called yesterday and spoke to collections dept at att. Woman said that they have done everything they can on their end that now erc has to choose to delete it. So... That's where I am. You may want to choose a different path.
If I could do it over again, i would call att eo with the mistake that they made (if they did in your case) and start from there. Get it in writing via chat, or something.
Good luck!!