Hi Md_Salem, As Erik Kostson correctly mentioned that you can use + on the contour color scale bar to increase the number of colored bands. I am adding some more details about this.
Simply choose “Shaded exterior and Edges,” as I mentioned in the attached image, and then click on the color band, wherein you will get a plus symbol (to increase the band of the selected color), and a negative symbol (to decrease the number of the band of the selected color). You can choose a new color by right-clicking on the color band and selecting it. After doing so, you will get the option for a custom color. To choose the desired color from the chosen color, click on the custom color. you can reset it all to the default Ansys band color by just selecting the option “reset all”. I have attached some images to show the above-mentioned process.