Thanks for the advice. I have done that and the lights that previously did not work now remain on permanently. I can use the dimmer and the switch for the other set of four lights, but oddly I need to use the right switch now to turn them on/off instead of the left switch.
So this confirms...
Hi thanks for your reply. Yep they were both working fine a few weeks ago then I went to change the switches to new ones and couldn't get it working. I then put back in the old switches but must haven't wired them incorrectly! So I'm sure it's just a case of getting them correctly wired again!
I have a two gang two way dimmer switch and two gang two way switch.
They are used to control 8 lights (4 each).
They are currently wired as shown above.
The lights operated by the left gang of the switch and the left gang of the dimmer work fine but I can't get the other 4 lights to work...