s3 cant detect sim after changing miui rom to kitkat rom

[DingDang EasilyForgotten]

Hii I've change my rom from miui to kitkat as my miui cannot be updated. My rom was successfully changed but the problem is that my phone could not read my sim. I went to my setting "mobile network" it says that "insert sim card to access network services". I tried to change my rom again but when I'm at my recovery page the other rom's zip that I tried to install it was be stated there "installation abored" and now I'm stuck at the kitkat rom with no sim card services, I didnt want to go to samsung service centre as I will definately be charge for rooting my phone before. Can anyone help????????