Question: How do I merge three duplicate contacts into a a single contact?
Solution: In Contacts you can use Combine Contacts under advanced tools to merge duplicate records into one.
Open Contacts and select the contacts you wish to merge. Click Tools, Advanced Tools, Combine Contacts.
Select the primary contact which the other contacts will be merged into. In this example I've selected the contact that has additional contact details.
Click Yes when prompted then you can review the log. Note that activity records are preserved and vendor links where applicable are retained to prevent orphaned listings.
The activity records from the deleted contacts are shifted into the primary contact's journal.
Duplicate contacts may be visible to admins on a centralised instance if a contact has been entered by multiple salespeople. For example if an office is running SalesPartner-Cloud, agents may have client overlap through entering open home visitors.