I have a very simple board with 2 components . I put them both on the top layer and they are correct. Pin 1 is 5v. Pin 2 is used for something else etc. As soon as I move the 2x5 pin header to the bottom, the pin rows are switched and I do not want that - basically pin 1 and 2 become 2 and 1 and pin 2 is now showing as 5V. Because it is a simple 2x5 header it is identical whether top or bottom. I am missing something really obvious here but can;t fathom it out.