Not receiving verification codes

dbf1001 has the answer! 

This happened to me on an iPhone 11 Pro Max.  No two-factor notifications came through. All regular SMS messages got through fine. I talked to technical personnel at all three banks that I could no longer log into. All said the same thing: two-factor code was sent out, but not delivered to my phone. Got a new SIM, reset network, restarted phone. No help. Then I followed dbf1001 advice: Called 611. First person to answer did not want to send me to tech support. Asked many questions. After patiently explaining what steps I had already taken, she connected me to tech support (about 15 minutes in). Tech support asked many more questions (Deos it happen only in one place? when did it start happening? do any other users have the problem? have you checked with the bank?) What finally persuaded her was that three different banks could not send me a short code. She then contacted someone in the back room who re-provisioned the phone. That did cut off the call, but they promised to call back. Phone indicator in upper right of screen said "SOS" where the signal strength and 5G symbol used to be. Powered phone down for 30 seconds, then restarted. All two factor codes worked thereafter. 

Success.  I just called the main support number from a different phone: 
1-800-331-0500

At the voice prompt I said I was having trouble receiving text messages.   It then transferred me to tech. support who knew exactly what the problem was and said lots of customers are having the same issue after a new update.   He had me turn off my phone so that he could "refresh and reprovision the phone" from his end.   When I turned it back on I tested with my bank and some other websites and it worked.   

Hope this works for you all!

I've had the same issue for at least a year but all of a sudden it got worse.  I couldn't transfer money from one bank to another or check my investment accounts so I finally decided to dig deeper for an answer.  I took the advice of previous posters here and called their 1-800-331-0500 number and suggested that my phone needed to be re-provisioned.  The customer service rep had me turn my phone off and on, called me back, and the problem was fixed.  So far I am able to get verification texts from everyone.  She said that she "reset" my phone, I assume she re-provisioned it as the other posters here have suggested.  Hopefully this has become a known fix for this problem among ATT customer service reps!

Called 611 and had tech support update/re-provision my phone and it solved the problem. I was not getting short texts (verification texts). It took 30 minutes with 2 different reps at tech support but I was immediately able to receive a verification from one of the accounts I've been unable to access. 

I had this problem while overseas and so not on AT&T network. The verification codes were coming in fine for a while, then one day they just stopped. I was not going to call AT&T support because I've had this issue in past years as well and they just don't understand it; I've spent many hours on long distance calls with AT&T only to have the make me try all kinds of nonsense things that I know won't work, and don't. I did once manage to get to someone who did something on the back end to fix it, I think maybe they reprovisioned the phone, but it took a long long time to get to that person.

So this time I tried something that worked. I went to Cellular Settings for the AT&T line and changes the Network Selection. It had been set to Automatic. I turned off Automatic and selected a different carrier than the one it had defaulted to. All of a sudden all my verification codes came through.  So, something to try if the problem happens when you are out of country.

I experienced the same problem the one described in other posts: could not receive SMS messages on my iPhone.  SMS had been working fine without any issues but stopped working suddenly a few days ago.  We had experienced a couple of power outages due to recent storms, and it seemed that SMS quit working sometime during the second outage.  I followed the suggestions and called 1-800-331-0500 from a different phone (a landline in my case).  After waiting on hold for about 10 minutes, I spoke to a customer support person about the problem and mentioned the refresh/re-provision suggestion.  He proceeded to do the refresh, and after rebooting my phone, a cascade of text messages flowed in.  I also tested it with one account requiring an one-time-passcode (OTP), and it worked.  So this appears to be the fix, and the AT&T representative was very helpful.

I just had the same “not receiving texts from shortcodes” issue.

Suddenly, for days, I could not receive one time passwords from Amazon at first and then Capital One.

Called Amazon. They said “call ATT”. 

After countless non-solutions (it’s not MY settings, guys) given to me by ATT tech support representatives AND HOURS OF MY TIME WASTED, one helpful (finally) rep…

[drumroll]

REPROVISIONED THE MESSAGING SERVER.

IT WORKED. 

I now can receive verification texts from shortcodes again. 

After this fiasco, I don’t think I trust using my ATT mobile phone number to receive verification texts any longer. 

I’ll switch to Twilio’s Authy app or (holding my nose) Google’s authenticator app. 

“You may live to see man-made horrors beyond your comprehension.”

- Nikola Tesla.

I just switched from Verizon to AT&T and now my short code texts won't come through.  My wife spent two hours on the phone with AT&T and no fix yet.  I will suggest the Reprovisioning solution next time we talk to them.  

I switched because of the price difference but now I'm thinking I'm getting what I paid for.  Never had an issue with Verizon besides price.  Given how long this has been an issue with people switching to AT&T (years) one would think they would have this figured out by now.  

Given how challenging this conversion has been for us I'm really kicking myself for doing it.

I do not receive text alerts. Thought it was my iPhone 12 mini so just upgraded to a 24 pro. Am having the same problem so I know it’s not the phone. Have checked all settings as did the sales lady at ATT.  How can I get this issue resolved?

I had the same issue on my iPhone 12 when we upgraded to an Unlimited plan. Installed a new SIM, reset Network Settings, etc etc etc. I finally had to get someone from the Office of the President to have them look deeper into my account settings and they found a corrupted file. Got it fixed and all has been well since. You should file a complaint with the BBB and then will get forwarded to AT&T Corporate who will turn it over to someone in the Office of the President who will contact you.