From my Samsung J7 , I transferred my UNITEL ( Angola) SIM card to my A30. In the J7, the SIM was fine but in the A30, I cannot activate mobile data. The network mode is stuck at 2G and I cannot manually input APN name. I can make text and calls but no mobile internet. I've tried help from UNITEL and they were not able to figure it out. Someone even said the A30 does not work in Angola (which most likely is not true).