iweb previous and next functionality broken

Hi. I have looked quite hard for the answer to this before posting. I have linked adjacent pages together on my iweb-designed website by using the 'previous and next' navigation links. The links work in iweb itself. On the actual website though, the links worked fine for a while, but now I've added some more pages in, the P/N links seem to jump around, skip out pages, or go round in circles. Anyone know why?

Thanks

Claire