CC2640: When the ccfg page is locked, how to flash a new image or erase the image?

Hi all,

I am now working on the protection of the page.

I found there is a define "SET_CCFG_PROT_31_0" 0xFFFFFFFF.

I think this is the protection of page 0-31. And I set the value to lock page 31(ccfg) 0x7FFFFFFF.

Now I got a big issue, that I can not write or erase image anymore.

The first time I meet the problem, I use the command line "srfprog -t lsidx(0) -e force" to erase it.

But the next time, this method did not work again.

Now I can do nothing but read...

Is anyone know how to solve the problem?

The log of srfprog is: 
Start flash erase ...

Flash loader reported an error(4)

Thanks

Peter