Matching by names and addresses is usually a nightmare if that's all you've got to match on. Especially as most systems let you put anything into the name columns. So you get Robert, Rob, Bob, Rab, R and R. supposedly meaning the same. And somebody called John in one table could be called Jack in another.
You need to get some kind of ID into each of the tables so that you can match on ID.
Even if the names were in the same format, you can't tell if they are the same person just by looking at the name. If you have more than one John Smith, how do you know which one is which if all you've got is the name?