baseband unknown

Operation: Repair
Selected model: SPH-L720
Selected port: COM633 Z3X BOX Serial Port
Software version: 24.2

Waiting ADB device… OK
Reading phone info…
Model: SPH-L720
Android version: 4.4.2
Product code:
Phone version:
PDA version: L720VPUFNG2
CSC version: L720SPTFNG2
CSC country code: USA
CSC sales code: SPR
HW version:
Phone S/N:
Modem board:
RF cal date:
Initialization AT RIL… error

Done with Samsung Tool PRO v.24.2

this phone was 5.0 before and was like this
i flash the phone to 4.4.2 but
cant repair baseband

help please