Before you proceed, you need InTouchApp installed on your phone.
How to export contacts from Web/PC :
Step 1 - Go to https://www.intouchapp.com/ and Login with the same details (as used on phone).
Step 2 - Click on the three-horizontal-lined symbol on the right side of contact category option.
Step 3 - Select Export contacts & select the format for exporting contacts (Outlook CSV, Vcf).
To use this feature, you will have to be on the upgraded account as it's a paid feature.