I found the middle two displays have one column both which will not light up:
I check the data sheet here: http://blog.pimoroni.com/micro-dot-phat/
I think it should be because of Pin 8. I did try to solder again on the Pin 8 on both display but still the same.
Any suggestions to solve this out?
Soldering:
Not pretty but seems to works on other displays
Tim