Unable to connect to 3G network

[abhi-nbmc]

ok so am using build 10536..the problem is my phone{lumia 1020} cant coonect to the 3G network...happened with the previous builds too..its in automatic mode and it only detects 2g..manually searching shows the 3g network available but doesnt work...its not a problem of my sim or the particular network thats for sure...please help anyone