I just replaced an iPhone 6 with a 6s. No problem installing IOS 10, Beta 2 after going through the necessary steps. The phone activated with ATT without difficulty. But, I am having a weird problem with iMessage, that I didn't have before. Apparently iMessage needs to be activated when it is first turned on in Settings. (It's on by default, but never seemed to get activated). So now, I'm trying to get it activated and it has been stuck for several days now with "Waiting for Activation" or "Activation Failed" messages. The send and receive messages shows my phone number greyed out and unchecked. I can manually check it, and the gear wheel just starts to turn but nothing happens except there is a sense of something trying to happen but its not happening.
This ramifies downstream to all my other devices, iPad, Mac, iPod Touch in that I don't receive messages on all the devices when they are sent directly to my phone. Regular SMS seems to work when I'm on the cellular network, and I can send and receive text messages from my OS and IOS devices as long as I am on a wi-fi network.
ATT cannot see a problem, but then I'm also using Beta software. They want to blame Apple and IOS 10, but I was using IOS 10 on my iPhone 6 without any difficulty, so I don't think it is a problem necessarily with IOS 10, but I'm somewhat at a loss to figure out what to do and where to go.
Any thoughts?