Error code -3 when flashing CC3200MOD

I am using a CC3200MOD board DIY and try to program this board by using uniflash via CC3200launchxl.

I try to connect as this processors.wiki.ti.com/.../CC3200MOD_Production_Line_Guide

Launchxl     -     My DIY board

P57              -      GPIO1

P55              -       GPIO2

nRST           -       nRST

GND            -       GND

SOP2 in my DIY board is connected to 3.3v 

Baudrate is 921600.

I get this error

[20:07:45] INFO: > Executing Operation: Connect
[20:07:47] INFO: setting break signal
[20:07:48] INFO: detecting FTDI for device reset
[20:08:04] ERROR: ---reading ACK signal failed---
[20:08:04] WARNING: ---seting break signal to false failed---
[20:08:06] INFO: setting break signal
[20:08:07] INFO: detecting FTDI for device reset
[20:08:22] ERROR: ---reading ACK signal failed---
[20:08:22] WARNING: ---seting break signal to false failed---
[20:08:24] INFO: setting break signal
[20:08:25] INFO: detecting FTDI for device reset
[20:08:41] ERROR: ---reading ACK signal failed---
[20:08:41] WARNING: ---seting break signal to false failed---
[20:08:43] INFO: setting break signal
[20:08:44] INFO: detecting FTDI for device reset
[20:08:59] ERROR: ---reading ACK signal failed---
[20:08:59] WARNING: ---seting break signal to false failed---
[20:08:59] FATAL: --- Can't connect to device !! ---
[20:08:59] FATAL: Error connecting to the device. Please check your COM port settings. Error code: -3
[20:08:59] INFO: > Executing Operation: Disconnect
[20:08:59] Operation Format returned. 

Could anyone help me to solve this problem? Thanks!