Firmware is not updated (VS-GW1600)

Good day.

I have your VS-GW1600 chassis and one VS-GWM400G module (GSM - M35) like this:
shop-gsm.net/files/products/vs-gwm400g-1...bb0baf168b04e8a54287

Model Name: VS-GGU-E2M0400
Software Version: 2.1.3
Hardware Version: Date 2012-11-09 FPGA 11 Hardware 00

I decided to upgrade the firmware to version 2.2.0

1. I did a factory reset

2. I tried to update the firmware via the downloaded file "wg400-current.img" from here:
www.openvox.cn/products/voip-gateways/gs...detail.html#download

I got the message:
"System Update Succeeded"
"You must reboot system to entry the newer system."

But after rebooting version has not changed... Nothing changed!

3. I tried to update the firmware via the Internet (System online update)

"Your current system version is :2.1.3
The latest system version is :2.2.0.
Be cautious, please :
This might damage the structure of your original configuration files!
Are you sure to update your system?
Your current system version is :2.1.3

Warning:
DO NOT leave this page in the process of updating; OTHERWISE system updating will fail!"

After rebooting I got the same result: Nothing changed!

Anyone can explain to me what I did wrong ?
Can I update firmware via SSH?

Hi Sir,
Normally it should be successfully update as you did.
Can you prepare remote access and let me check?
My skype is as follows.

problem solved
Thanks for the help Tim.June
I flashed the device through the serial port using rs232 ttl converter