You live with your characters every day. BUT if you met them on the street, would you find their conversation boring? Would you even want to know them?
Or is their dialogue clunky? Do they say too much? Not enough? Or even worse, the obvious? Does their dialogue lack conflict or subtle tension? Dialogue should be 50% or more of your novel. It can foreshadow, advance your plot and give back-story.
There are specific tools that you can use to make it flow- snappy, poignant or somewhere between. This two hour Studio will give you those tools and let you practice using them.
Pay in advance at http://penpaperwrite.com/studio-series/