Thunderbolt 3 dock not charge X1 Carbon 5th Gen

Hi, all. I have a problem thunderbolt is not charge notebook, but usb ports and displayport working.

1. I connect the Laptop with the Thunderbolt connector on the backside of the Dock (beside the HDMI/DP connectors) and on the frontside, not working.

2. I updated all drivers.

3. I go into the BIOS and "disable the battery for technical service".

But if I use an AC power adapter, it charges.

Does anyone have a solution?