Not found a good auto system yet, think that is a major gap in the market, although I think the Family Insight app could be useful. It has a trial period.
If you are only dealing witha few individuals though, it's not so difficult to use the PAF facility to merge them. Save the existing data file as a back up somewhere first, then use the tools/match merge option. You can play around with the various options but usually comparing by eye should tell you whether you are looking at the same person twice, or not.