请问各位大侠,铺铜问题

请问各位大侠,铺铜问题,我现在做一块6层板,都是正片,最后我想在TOP层,BOTTOM层各铺一层铜

但我怎么也铺不上去,状态显视Done dbdoctor.
Shape moved from a null net to SGND.
Clines previously connected to shape will have to be resolved.

不知道是为什么,请各位大侠指点,

在线等