UNABLE TO CONNECT, CALL DROPS, POOR CONNECTION - WHILE ON WIFI

It could be that your account was not provisioned correctly, or at all, for HD Voice. Enable WiFi Calling on your phone as well as WiFi. Completely power off your phone and then power it back up. If you are connecting via WiFi-C, the alpha tag on your phone will indicate "AT&T WiFi" next to the WiFi signal strength. As previously mentioned, the phone will connect to the strongest signal, which can vary as you move around your home, so you may lose a call if the connected signal goes from WiFi to cellular or vice versa. There is no way to force the phone to use one connection method or another.

Thanks. I didn't even know there was a HD Voice. How/where is that enabled?  WiFi Calling is enabled as well as WiFi. Powered off/on. I don't know what WiFi-C is. All I see in the upper right corner of the screen are the bars, WiFi signal strength and battery strength indicator. Nowhere does it say  "AT&T WiFi". So far today, no issues. The connection problems seem to occur the most during the weekdays during business hours.

@mcs2015 WiFi-C is short for WiFi Calling. Your line/account has to be provisioned for HD Voice by AT&T. The only setting on your phone would be under the Phone Settings -> WiFi Calling. If WiFi-C is enabled on your phone and your phone is connected to your home WiFi, then WiFi-C should work and that would be indicated by the "AT&T WiFi" alpha tag next to the signal bar strength indicator. If not, then your line is not provisioned and you can't use your home WiFi to connect to the AT&T Mobility Servers.

What kind of phone do you have and is it a prepaid or postpaid account?

Still don't know what is meant by "updated your SIM profile". Please explain. 

As to AT&T HD Voice, no one @ tech support ever mentioned it before. How long has it been available? This coverage map shows I am in the coverage area: https://www.att.com/maps/wireless-coverage.htmlhttps:.html 

Do you think HD Voice will solve the spotty connectivity, call quality and call drops that have been plaguing me for the last couple months?

I have a iPhone 12 Pro postpaid account.

HD Voice is AT&T's term for VoLTE. It has been around for a few years now. If you are in an area that can receive it (most can I believe), you have a post paid AT&T account (that may not even be a requirement now), and a phone that is capable of WiFi-C then you should be able to do WiFi-C. iPhone 12 Pro's are capable of WiFi-C (I have and iPhone 12 and WiFi-C works perfectly). 

I don't know what "updating your SIM profile" means either. I assumed it meant that AT&T was checking to see if your line was provisioned for WiFi-C. 

What kind of internet service do you have?

Yes, I already have WiFi-C for the last few years. It has made no difference. I still am getting all the aforementioned issues. ISP is Cox Communications. There service shows zero issues.

If you do have WiFi-C, and are still getting dropped calls and poor voice quality, it probably is Cox. Cox will never say it's their service but my guess is that there is an upstream switch somewhere that is faulty or one of the ports necessary for WiFi-C is blocked or having issues reaching the AT&T Mobility Servers.

WiFi-C on Apple phones requires port 4500 and port 500 to remain open and trouble-free. If there are issues with either port, you will have call quality issues. It also depends on how robust your WiFi connection is.

I am still intermittently unable to connect from incoming or outgoing calls. No indications on the bar strength or otherwise to determine anything. Not being able to determine the cause is so terribly frustrating. Sometimes I have to initiate a call several times to get it to finally connect and start ringing.

Ask Cox the check if there is anything amiss with ports 4500 and/or 500 and make sure your router is open to those ports. Don't expect much from Cox tho.

Also make sure they didn’t set you up as a business account. I have charter and unbeknownst to me it was set up as a business account causing me to get banned from gaming servers   Wi-Fi calling dropping. Websites not loading. As soon as they made it residential all issues went away. The easiest way to check is to run a Speedtest on Speedtest. Net. It will say in the results if it’s a business account.