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The Samsung Galaxy S24
bachslap's profile

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Tuesday, May 23rd, 2023 3:38 AM

New phone not showing AT&T at startup, no voicemail number, no 5G..

I got a refurbished Galaxy S20+ recently with a brand new AT&T physical SIM card in it.  I can make phone calls and use mobile data, but unlike my partner's S20+, there is no AT&T screen at startup, no 5G logo when connected to the network, only LTE, and when trying to set up voicemail, I get a message saying there is not voicemail number.  I called AT&T customer service and registered the IMEI number, and I can now see my device listed on our account page, but it has no recognition of what kind of device it is.  After doing some reading, I've seen people suggest that maybe the CSC is incorrect.  I checked and it is showing a code for a different country and service provider (Koodo).  I tried using *#272*IMEI# but got an error message, and I am hesitant to try using Odin to flash the firmware.  Is there something I'm missing?  It seems like the phone mostly works but is not completely working with the network.

Accepted Solution

Official Solution

Community Support


232.2K Messages

1 year ago

We're happy to help with information to resolve your concerns bachslap.


Thank you formerlyknownas for the helpful information.


There are many versions of the same phone, and each version has its own model number even when the marketing name is the same. You can determine your phone's model by Going to Settings>You may have to go into the System menu next> Tap About Phone or About Device to view the model name and number. 


We recommend checking the AT&T Wireless Coverage Map to confirm 5G coverage. Next, please power cycle your device and reinsert your SIM Card to reset your device. Also, reset your network settings to refresh your connection. 


Be sure to set up your voicemail within 60 days of activation, or it’ll be automatically removed from your account.

  1. From your wireless phone, press and hold 1 or the Voicemail key.
  2. Select your language preference.
  3. Create a 7 to 15-digit password.
  4. Select your preferred greeting.
  5. Listen to the brief voicemail tutorial.

If you're stll having issues with setting up your voicemail you can get step-by-step help to fix voicemail issues. Please sign in to get started.


We understand the importance of staying connected. Let us know if you have any questions. 


Marilyn, AT&T Community Specialist

ACE - Sage


117.7K Messages

1 year ago

Ideally you should always do an IMEI check whenever you bring your own device

If it says it's compatible, and you are able to make voice calls and use data, consider it a win.  If you can set up Wi-Fi calling, it's a double win.  It would not surprise me however if neither Wi-Fi calling nor 5G work on an unlocked device.  * (See link below)

This is likely an unlocked device, not carry your branded which is why there is no AT&T boot screen.  

If you previously had set up AT&T voicemail, you should be able to set it up on this device by either setting up visual voicemail or press and hold the one to set up call in voicemail

If your voicemail account was not set up, you may need to call AT&T to have your voicemail account reset.  

AT&T does not offer transcription and it is not built into Samsung devices. If you wish to have visual voicemail with transcription, get yourself a free Google voice number and forward your calls that are unanswered or missed to your Google voice number.  I like transcription, so I've been doing it this way for several years.


Service capabilities of unlocked devices

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