You can edit, modify or change the name and details of saved contacts on Web/PC easily.
Before you proceed, you need InTouchApp installed on your phone.
How to edit contacts on Web/PC :
Step 1 - Go to https://www.intouchapp.com/ and Login with the same details (as used on phone).
Step 2 - Search for the contact in the search box
Step 3 - Click on the drop-down arrow on the left side of the contact photo and select 'Edit'.