With windows phone often you will run into an issue of duplicate contacts (though windows phone automatically links related contacts) because you will have different contact list added from different accounts. However, you can also manually link the contacts which are duplicated.
- Open any of the duplicated contact.
- Tap the link icon.
- You will be provided with suggested contacts if there are any with similar names.
- Or you can also tap the “choose a contact” to choose any other contact to be linked.
- Once the contact is linked, you will see all the updates under the same contact.
The same way you can also unlink a contact.