Thank both Boffin1 and CrossRoads
I have tried your code suggestions and it works fine to display numbers 0 to 7 and 9 but the display still goes blank for 8.
I will post a link to a video I have uploaded on youtube. I think there is something wrong with my schematic but I am not sure.
Boffin1 I have ordered some TPIC6B595 as it has the darlington transistors built in. I am not sure but could 74HC595 being 8bit and ULN2003 only having 7 inputs/outputs could be causing thisproblem?