Samsung Galaxy S3 Not Receiving Calls - Phone issue or Android issue?

@ M.A.S.E lol i saw you in a forum asking about something , just want to say i have being use it for a week now and i love it , but i think lte still might be and issue , the few time i used it was cool, but still not want to risk leaving it on lte all night and miis call.

m.a.s.e: You paid full price for the phones and still have a contract? I thought when you paid full price for the phones you don't have a contact?

OMG ATT is the worst company i ever had the un pleasure of talking to tech support. 

i called again to ask status, let me not start that the rep had NO idea what i am talking about and again told me i need to replace my sim,phone,life,car,fridge in order to trouibleshoot this. 

after i begged her to check this forum, check the bazzilion case numbers i have and she kept on refusing i asked for her to simply unlock my phone so i can get the F our of ATT

to my surprise she said "no, u need to pay the ETF in order for me to unlock your phone"

there are no words to describe how much i despise ATT right about now. 

luckily there is XDA developers, and we can easily unlock our phones without the need for ATT. 

this is by far the worst experience i EVER had with a customer service. 

and yet ,there is zero help on this matter from ATT. insane

I’ve been battling this problem for several months.  I bought three new Galaxy S3 phones and they all have the same problem.  I’m missing many calls and if someone bothers to leave a voicemail do not get a voicemail alert for several hours.  The phones work fine for outgoing calls, but not for incoming calls.  Incoming SMS and MMS messages are delayed for several hours.  When I place an outgoing call, the phone works fine for a few hours, but eventually locks up and stops receiving calls and messages making it a difficult problem to flush out.

I’ve been on the phone with at&t at least 30 hours over the past several months and my energy is drained.  I’ve sent one of the phones back to Samsung for “repair” three times and the problem still exists.  Samsung basically replaced the entire phone by the end of third trip to their service center.  I sent it to Samsung because at&t said their warranty only covers sending me a refurbished phone with possible dents, scratches, and/or blemishes.  I bought three new phones and I will not accept at&t’s refurbished phone policy.  Any replacement phone would have the same issue as well, because the issue is with the at&t network.  I travel extensively and the problem exists no matter where I’ve been in the USA.

They have to be aware there is a very serious problem with their network.  I find it almost impossible to believe they don’t know very well about this problem.  It is beyond aggravating to go through the same games on the phone with their tech support every time I call in.  It takes a good 30 minutes to get them to the point where they’re not asking questions such as “is your ringer volume turned down?”.  Verizon should capitalize on this and do a commercial explain at&T’s failing 4G LTE network.

I’ve tried many alternative APN’s and configurations, but all have one problem or another.  Some won’t work for hotspot, some are not any better than the factory settings, and some seem to work better, but still drop off the network for 20 seconds every 5 minutes.  If I try to place a call during this dropout period, I get the “EMERGENCY CALLS ONLY” message, and certainly any calls that come in during this drop out period are missed.

I’m now trying the “pull the sim card out and dial *#2263# method”.  So far it is working, but I also do not accept this as a solution.  If this fails, I’m flying to their HQ and discuss this face to face.  It’s not a matter of money at this point… I just want my phone to work no matter what the solution.  If another carrier had worldwide coverage, I’d switch in a heartbeat.  I don’t care about ETF or collection agencies… I need a working phone.

This solution won't work on my S3 because when I pop out the SIM card as instructed, I get a popup telling me my SIM card is out and my only option is RESTART. I'm unable to access the keypad to dial #anything, much less disable LTE. Anyone else have a viable solution?

My wife and I both started experiencing this issue before either of us had upgraded the OS, so I don't think it's an upgrade issue.

I also don't believe it's a hardware issue because a) I had my S3 replaced and it continues to miss calls and texts, b) my wife's Samsung Captivate has started to do the same thing and c) it started happening before either of us upgraded the OS. It also wasn't happening for the first couple of months I owned the phone - it only started happening after LTE came into my area. And it certainly wasn't happening for the last year that my wife has had her Captivate.