Hi I recently got a mini one dual sim phone from China. I am able to use one of my sims (TSTT) but not the other one (Digicel). I live in Trinidad. Nothing is wrong with the digicel sim as I am able to use it in other phones. Can this digicel sim be locked? If so how do I undo it? IMEI :355757010015614 IMEISV : 78
check from the GSM Coverage Map, we know Telecommunications Services of Trinidad and Tobago Ltd (TSTT) GSM 1800 and Digicel Trinidad and Tobago Ltd GSM 850/1900 obviously, your phone is only dual band, not tri-band or quadband.