Now you can merge duplicate donors together. Just click on "Contacts" and then "All Contacts". Find and select the donor that you want to keep, and then click "Merge Duplicates" in the right-hand menu. The next screen will suggest potential duplicates based on the donor's name, or you can search for donors using the search field. Click "Merge" next to the record that you'd like to merge.
All the information from the two donors will be merged together, including their address, donations, and recurring donations.