How can I enable DM port on WP7608?

I have already used AT!USBCOMP for disable the DM port(I didn’t see the message “It can be
disabled on WP76xx/WP77xx, but cannot be re-enabled.” at that moment).

I trid to use AT!BOOTHOLD for disable the DM port for a short time(before next power on),and used swiflash to flash the spk file to my device.
But when I done this, and power on my device, the DM port is still disable.

Does anyone know how can I keep my device’s DM port enable for all time?

Sorry for my poor English.

I am using DM port for the last two years on WP7608. I think it is not a big issue. At the first time when use DM port I facing the same problem, I can’t find the proper solution. Then I got the solution by following

Thanks for your reply.
In my country,actually,I can’t access to .