Shelly UNI 24v to 12v

I have recently installed a Shelly UNI on my Solar Gate batteries. I have connected the two red and black wires 1 and two to 24v power supply.
I connected the white wire pin 3 to positive 24v and the green pin 6 to ground
All my reading are showing 14.42 volts when meter at 26v.
Anybody have an idea as to what I’m doing wrong?
Thanks in advance.
Fox

24V +DC => Pin 1 & Pin 3
24V - DC (GND) => Pin 6