I took photos with Kimbe dm2-400 flash camera, and the camera is D3 100. Before connecting the flash device, I took pictures outdoors, one flashing and the other not flashing.

That's because the flasher is dead or out of order.

From your description, it seems that there is no electricity, it is very cold outside, and the receiver battery can't work. When the indoor temperature is high, the battery power is slightly recovered, but it is close to dead, so it does not flash.

If you glaze ceramics, the reflection should be small, the light ratio should be small, and the outline should be clear. Try the polarizer.