cant save data in flash on DFU reset_prepare function

[makouda]

im using nrf51822. before entering DFU mode I want to save data in flash. but when I call pstorage within reset_prepare function, it doesn't jump to DFU mode !!!!

reset_prepare(void)
{
   /* code */
    err_code = pstorage_block_identifier_get(flash_handler, block_id, block_handle);
    err_code = pstorage_clear(block_handle, size);
    err_code = pstorage_store(block_handle, data, size, offset);
/* remaining code */
}

[makouda]

no i dont use debugger !!!!!