I recently unlocked my Samsung SGH-T139 from T-Mobile. I put the other carrier (Cricket) SIM to test to see if it will work and the phone is in a constantly "Searching" state. If I pop the T-Mobile SIM in it works. I checked to make sure it is unlocked all the settings show it is. I even manually hard reset the phone. When I try and do a manual network selection in the menu it refuses to connect to the Cricket network - gives me a "not allowed" error. Google searching hasn't been able to aid me in getting things working. Any help is greatly appreciated.
It sounds like your phone is unlocked but can’t connect to the cricket network. Looking at the specs for the T139, it only supports network bands GSM 850 / 1900. You may want to check with cricket to see if they have those specific frequencies in the area you are trying to use the phone in.
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