It sounds like keyword cannibalization, except you'e saying "unique" content on both.
--> I had already solved this issue.
But I'm guessing you just mean they aren't literally copies of each other. Topically, I'm sure they are the same. So it is likely an intent thing. Google is serving one of the two pages based on what they think the searcher's intent is. Is one page more informational and the other more transactional?
--> My both page are servicing same services but my competitors are also doing the same and getting rank for each page with desired keywords..
Make a spread sheet of the search data: the queries and which pages rank for which, and try to look for clues. Plug the pages into TextOptimizer - that tool will give you an idea of how your content might be interpreted.
--> I will try this method too
Knowing the differences between the two pages will help, because I'm sure they are not as "unique" as you think. Good luck!