TMS320F280025C: TMS320F280025C can't load code in Flash after built with Flash_lnk.cmd

I download C2000ware SDK , and we use TMS320F280025C board and the example of TMS320F280025C from SDK .

but when I download code to chip Flash after build project with Flash_lnk.cmd, it reminds dowloaded successful , but the LEDs didn't show any light . 

and when I donwload code to chip ram after build project again with Ram_lnk.cmd, and the LEDs lights shine . 

I didn't modify anything about the code , just build with Flash_lnk.cmd or Ram_lnk.cmd , but it seems the code didn't load in Flash .

need friends helpful and warmful answers and advice .

Thank you