Welcome @hiraksarkar
So far you didn’t get any response, probably because it would be much easier to look for a solution if you would provide some MWE (see Please read: make it easier to help you).
Despite that there are some obvious issues: you use df2 in the second scatter plot instead of df and strings as colors do probably not work per se, they need to be converted, and it should be color=df.ncv_color, or df2.color it df2 was intentional.