Iphone 3gs won't connect to 3g, but edge works everytimes.

[Depressionused]

I use to be on 3.0 when I bought the 3gs and even unlock/jailbreak it. It worked out fine but recently, my 3g internet is not connecting well. I use to put tether option on the phone but I don't know if that cause the connection problem. When ever I turn on 3g, I get no service for awhile then it connect but only for a few minutes then it receive problems. 3G icon is still on the status bar but it won't connect. Could anyone help me?

Right now, I'm on 3.1.2 jailbreak and I thought this update will fix the problem but it's not.

[Cowboy]

try resting the network to this is it is
settings>general>Rest>rest network

[Depressionused]

I do it every times when try to fix the problem. It work for a minute then it just fade away and freeze trying to begin loading a website. But the 3g icon is still there.

[Cowboy]

I would take it to apple sounds like antenna problem

[Depressionused]

i think i got it working. I justgo back to restore 3.1.2 and use it for awhile to get use to the settings and then jailbreak it with cautions. Install cydia and thats it. I have less problems now. thanks you.