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Caller ID (incoming) not working. AT&T is not getting the name to display.


Caller ID (incoming) not working. AT&T is not getting the name to display.

Recently (within the last few weeks), many calls, especially those from cell phones, only display the number and not the name. (Various phones will display different things when that happens, for example, blocked, out of area, etc. or maybe the city of the call).


After talking with T-Mobile (my cell phone provider) they told me to talk to AT&T. AT&T told me to talk to Neustar (the company that manages the caller ID database). Neustar was helpful even though they normally don't work with consumers directly, but only with phone companies.


After a lot of work and various research, the way caller ID is implemented from cell phones, etc., is as follows.

Unlike the way it worked 30+ years ago where one central office (CO) would send the phone number and name to the destination central office, now typically only the phone number gets transmitted. This is partly because the cell towers don't have the information. Then the CO at the called phone has to look up in a database the name for that phone number and send it to be displayed.


That used to work but stopped a few weeks ago for me.

It works for me if I call (from my cell phone) to a Comcast line. Comcast looks up the name and displays it. Neustar could see the database lookup requests.


But when I call my AT&T landline, nothing displays. Neustar said that they are not getting any database lookup requests!


This happens to me from many callers, almost always from cell phones.


As I said, it used to work until just a few weeks ago.

We suspect that the local CO is mis-configured and is not requesting the data, or has a routing error.


It can very frustrating. I use the name to help be decide whether a call is legitimate or spam. Even when my son calls me, his name doesn't display. But when daughter calls me (from an AT&T cell phone) it displays correctly. AT*T has some of there own databases and that is probably why my daughter's displays. But they are supposed to query Neustar for non AT&T phones.


As I said, this only recently started happening. I have been frustrated trying to get to someone technical at AT&T to fix this.

As I said earlier, one AT&T engineer had me talk to Neustar. He understood technology but assumed that the database at Neustar is not correct. But it is! The problem is that AT&T (at least at my CO) is not sending the database query.

Anyone from AT&T who can help me?

Message 1 of 3

Re: Caller ID (incoming) not working. AT&T is not getting the name to display.

Well, I got AT&T to fix it. It turned out it only failed when getting calls from T-Mobile phones to AT&T landlines. It took me numerous calls to T-Mobile and AT&T including calling the AT&T CEO's office as well as providers of CNAM services (caller ID name service companies) before I could finally get everyone to work together to get it repaired.


For the AT&T switch experts out there and other interested techies, AT&T had their switches configured incorrectly. What was going on was an invalid "lnp-serv" entry in their STP (Signal Transfer Point) that apparently had been there for some time. Essentially that bad entry was causing the routing for the CNAM lookup message to get overlaid with bad data. That would result in it being sent to a destination for which there was no route. It then would get dropped on the floor. What AT&T had to do to fix it was simply to remove the bad entry and then the routing worked fine.


They have fixed it in the old Pac Bell service area (mine) and also have fixed it now in the old Southwestern Bell and Ameritech service regions as well. I don't know if they have or will make sure it work in the entire AT&T system but at least my landline now displays caller ID correctly.



Message 2 of 3
ACE - Master

Re: Caller ID (incoming) not working. AT&T is not getting the name to display.

Good information, thank you.👍

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*The views and opinions expressed on this forum are purely my own. Any product claim, statistic, quote, or other representation about a product or service should be verified with the manufacturer, provider, or party.
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