Creating a map with multiple variables

I have been trying to add another variable to my map currently I haven't been able to add the second variable which I want to be "MasksMandatory" which I want to create outlines for whether Masks are mandatory or not around the countries. I have inputted what I think is the correct code which is in the screenshot below. Would anyone be able to point me in the right direction?

It looks like color = “black” within geom_polygon. Try moving color inside the aes() call and set color = MasksMandatory. This should allow scale_color_manual to take effect.