mobile

Hi, i'm new with all this and the android stuff, but going to the chase, i need help from someone. I have Sony Xperia M2 D2303 Android KitKat 4.4.4, not rooted and bootloader locked which means i can't install CyanogenMod 12 due to my locked bootloader. Can anyone help me out? Tell me how to unlock the bootloader or how to install CyanogenMod 12? Note: My bootloader is not allowed to unlock.

Please.. Just help me with this :(
Thanks