[Q] Error "not registered on network" need help topic

hai, any one can help?
after flashing bootloader dan baseband i got error "not registered on network"
i've read on several thread i've check several things
- Serial not null
- Imei not null
- baseband recognised as DNK3

i've done flash back to stock rom now and result
- Serial not null
- Imei not null
- baseband back to original stock my region DNG1

but it's still error :(