Disable a Flag on a Contact.
Steps
Go to the My Apps
Select Contacts
Look in the Flags column of the Contacts App overview tab
Each type of flag has a different colour as set by your Organisation Admin
When you see a Flag, click it
A small popup appears that displays the information within that Flag
It tells you
The status of the Flag: i.e. whether it is enabled or disabled
Which user added the Flag to that contact
When the Flag was added to that contact
Information about why the Flag was added to that contact
Press the Disable button
A popup box appears asking you to confirm whether you want to disable the Flag or not
Once the Flag has been disabled on that contact, it becomes grey