Sorry to see that, searover. I'm eager to help you resolve this matter with your contact as well. The good news is you won't have to delete the entries one at a time. Do you use Verizon Cloud to back up your contacts? If so, you can log in to your My Verizon Online account and check all duplicate contacts and delete them with minimal keystrokes.
As for preventing this from happening, it's tough to say without knowing what caused it. A step I would recommend for this particular contact would be to jot down or print all info related to it and then delete it entirely. You can re-enter it afterwards.
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