HeatMap Color Formatting

I have a heatmap as below:

I want to change the color for the data ranging from 0-1600 (i.e in blue color) to green color. I tried doing it by selecting the heatmap and changing it through "Displayed Series Format" option under "additional properties window". But its not changing the color.

Another try I did is, I changed the color using conditional formatting but it changes the color in heatmap but not the side axis part where the data is given.

Any suggestions or answers are welcome!

Thanks!