If some contacts were merged my mistake you can unmerge them now. This will separate all the details of the contacts including stories, skills, flags, relationships, projects, tasks, and notes.
You need to be an Organisation Admin to do this process.
This functionality is only available for contacts that are merged after 10th of October.
Steps:
Go to the Contacts page by selecting Contacts from the My Apps menu
Click on More Options button
From the dropdown, select Merge Contacts to go to the Manage Merge Contacts page.
You will arrive on the Manage Merge Contacts page.
You see a list of all the merges that have been done. Find the contact merge you want to unmerge and press the Unmerge button corresponding to it.
Press Ok for the prompt confirming the process.
The Unmerge process will start.
Once it is completed, the contacts will be separated.