ISsue with polylang changing to default language

I am currently developing a website which uses different regions e.g. Asia/Pacific and Americas etc.

Most of the pages on the site will be translated to all regions but there will be some sections of the site which do not need to be translated so there will only be one language for those pages.

The problem I have is that if you are in a specific region/language and then go to one of the pages which is in the main language then it will take you out of that region and into the main sites one.

What I would like to happen is for Polylang to save a cookie for the selected language then when the user goes to a page which has not been translated into other languages they will still see their language selected and menu etc.

I hope this makes sense, and I am sure I am not the only one with this kind of problem. If anyone can help at all that would be great thanks.