HERCULES-F021FLASHAPI: TMS570LS3137 Flash API "Fapi_issueProgrammingCommand" number of bytes

Hello,

i am using "Fapi_issueProgrammingCommand" command to program on-chip flash of TMS570LS3137 micro-controller. observing a behavior where i am asking to program 4 bytes and observing "0xFFFFFFFF" data in memory browser of CCS 8.0.0 next to the programmed address. Below is the command issued: 

Address to which program command is issued - 0x00180018

data buffer a array of bytes with length 4 bytes.

pu8EccBuffer      - 0

u8EccBufferSizeInBytes - 0

oMode - Fapi_AutoEccGeneration

could you please help me to know the reason for this behaviour?

Thanks,

Kalyan