Unjoining Contacts

You did not mention your phone. The menu may differ for every phone brand or UI. On a Samsung, open the contact details. You will see a row of icons representing the joined contacts. Click that then you will have options to unjoin contacts.

 

I have a problem when I try to unjoin contacts on my Samsung Galaxy SII 4G Boost Mobile with jelly bean upgrade. I go to the rows of phone icons in the contact and tap on those and a screen comes up where I tap a red minus sign to unjoin a contact and tap save. But the contact stays joined.