Not able to display anything on LCD "NHD-C12864WO-B1TFH#-M"

I am currently evaluating NHD-C12864WO-B1TFH#-M for a new project.
I have taken a look at the sample code and implemented accordingly.
I got the sample code from Newhaven site:
https://github.com/NewhavenDisplay/NHD-C12864WO_Example/blob/main/NHD-C12864WO/NHD-C12864.ino

However, I am still not able to get the display to display anything.
To make debugging easier, I have used the command "Display all points ON" to display all pixels black after LCD initialization.
After sanding the command "Display all points ON", the LCD still displayed nothing.

Below is the LCD initialization sequence after device power on.

comm_out(0xA2);            //LCD drive voltage bias ratio.
            comm_out(0xA0);            //Ram->SEG output = normal
            comm_out(0xC0);            //COM direction scan = normal
            comm_out(0x40);            //Display Start Line
            comm_out(0x25);            //Resistor Ratio Set
            comm_out(0x10);            //column address set (upper bit) Double Byte: 1 of 2
            comm_out(0x00);            //column address set (lower bit) Double Byte: 2 of 2 
            comm_out(0x81);            //Electronic Volume Command (set contrast) Double Byte: 1 of 2
            comm_out(0x25);            //Electronic Volume value (contrast value) Double Byte: 2 of 2   
            comm_out(0x2F);            //Power Control Set
            comm_out(0xAF);            //Display ON
           
            comm_out(0xA5);            //Turn all points ON

I have also attached the LCD related schematics and the signal timing when the command "Display all points ON" (0xA5) is sent to LCD.
From the signal timing, everything looks good when comparing the the datasheet.
Is there additional that I need to do to get the LCD working?