I have an unlocked debranded 6620 with firmware 4.22.1.
It works ok except that none of the # codes for T-mobile work. They all immediately return "Request not completed". It does not appear that the phone even goes out to the network, as the response appears less than a second after pressing send.
Even worse than that, attempting to dial 611 causes the phone to freeze hard for about 30 seconds, after which "Call not allowed" appears.
Therefore, there is no way for me, from my phone, to check minute usage or work with my plan at all short of calling T-mobile's tollfree number or something!
What's up with this? Any ideas?
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