L720 Domestic Unlock Problem, No signal no internet

I am having a problem with a Sprint Galaxy S4 after domestic unlock, It has no signal and no internet, i made sure my SIM is good and serial is good. The signal bar has an X over it.

– I make sure Network mode is GSM/UMTS

Model: L720
Version: 4.4.2
Baseband: L720VPUFNG2

can someone help me troubleshoot it?