Unwanted transparency [SOLVED]

I’ve run into a problem which is a drawing group is in transparency mode. I can’t find any transparency nodes used and the layer opacity for the drawing layer is 100%. Moreover, i tried to change the composite mode and still can’t get rid of the transparency.
Am I missing something? Any guidance would be very appreciated.

Is the transparency there in render mode? Do the drawing layers have transparency in settings? Maybe light table has transparency on for line/bitmap/etc?

Finally solved the issue. It was the color palette of the drawing is transparent.
Anyway, thanks for ur reply.