Shadow format lost when assign ColorFormat to specific CategoryPoints

[earlykind]

Hi everyone,
I have original slide setting all format such as color or shadow.
And then I have to change their format to individual points based on the input.

In my case, I tried change line's color in the combo chart which has shadow.

1. First I change the Series color format from yellow to dark blue [x-axis = 2014-2017]
   In this case shadow is still show
2. Then I tried to change only some points[2018-2020] to dark pink
   but the shadow for dark pink line is missing.
   Is there any work-around to change color,format to individual point in series and maintain its shadow
   I already tried reading library document but I can't find way to set shadow to chart series or point.

Origin slide:

Result:

[scanny]

Please provide the minimal code that demonstrates this behavior. https://en.wikipedia.org/wiki/Minimal_working_example

[earlykind]

Here is the example of my code with brief explanation

chart = shape.chart
#Retrive line serie from chart data by name
targetSerie = [x for x in chart.series if x.name == 'LineSerie'][0]

## In case of Changing entire Series color
fillFormat = targetSerie.line.format.fill
fillFormat.solid()
fillFormat.fore_color.theme_color = MSO_THEME_COLOR.LIGHT_1 ##My pptx theme color set this one as dark blue
## as I mention before using above to change entire line serie's fill, shadow is still show

## In case of Changing only some point in serie
for i in range(start_point,len(targetSerie.points)):
    seriePoint = targetSerie.points[i]
    fillFormat = seriePoint.line.format.fill
    fillFormat.solid()
    fillFormat.fore_color.theme_color = MSO_THEME_COLOR.HYPERLINK ##My pptx theme color set this one as yellow
##After I ran this code to change some part of lineSerie from dark blue to pink, the part which to pink lose its shadow format