Downloaded image is appears Black and White, instead of being coloured

[SohamIITK]

I am using this for the first time. I want to draw a photodiode device which has a multilayer film stack (silver, ZnO, Y6, Rubrene, etc.) and I want a coloured image. Initially, when I tried with just silver and AgO, I got the correct coloured image as shown:

Then I just copied ZnO layers and changed the colours as well as text, but it turned out to be like this:

Whereas, it should have looked like this:

I tried making a new one from scratch but I kept getting just black and white images! Can someone please help me with this?