cant receive or send text messages on 3gs ios 6.0.1
I have a jailbroken iPhone 3GS with iOS 6. I restored my phone to factory settings with iOS 4 and baseband of 6.15 (iPad baseband, right?). I then updated it to iOS 6, but can't get past the activation since it keeps telling me that it can't detect a sim card and it's "temporarily unavailable" when activating through the phone. I read that I might need to jailbreak it in order to get past this and unlock my phone. I did (and downgraded it to 5.14.04 with redsn0w since I found out that this was causing my low bars for service and other problems) , and was able to get past the activation, but can't get service. It says 'No Service' when I'm supposed to have service. I then followed a guide to download ultrasn0w fix and ultrasn0w in order to unlock my device. It worked for me (was soon surprised that it wasn't supposed to work with the redsn0w downgrade) and was able to get service. I was able to receive and make calls, but wasn't able to send text messages and if I receive text messages, I get 'Unknown' as the sender and the message is always blank. I thought this problem was the effect of my firmware not being compatible with ultrasn0w. I then upgraded my baseband back to 6.15 because the guide stated that 6.15 is supposed to be compatible with the trick. After upgrading, I was also able to make and receive calls, but had the same problem with text messages. I can't send messages and when I receive messages, I still get the 'Unknown' contact and get blank messages.
I've seen others getting this problem, so I don't think it's because of my phone.
I really hope you guys can help me and thanks in advance!
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please help me out