Phone shows wireless connected but data plan is being charged
I have an iPhone3g and have had no problems using it on the wireless connection at home until last month. I got a notice near the end of the month about being close to my limit and realized the phone wasn't auto connecting to wi-fi. After searching the forums, I found a suggestion to back up the phone and then reset the network, which I did.
Since then, I have checked the network setting every time I start to play WWF or something on the phone and it shows that I am connected to my 2Wire network. The icon on the menu sometimes shows up, sometimes not, but the setting shows that it's connected. (My usage pattern is very consistent, btw, so no change there.)
The usage reset on 8/24 and today I got the text that I'm already at 65% of my data plan. I checked the usage chart and apparently am using data even when my phone shows that it's connected to the wifi network.
Have you heard of this before? As I said, the problem is new and nothing has changed hardware or software-wise. Is this something that might "wear out" on an iPhone or is there a fix I haven't found?