I don't think they have dedicated service centers like other companies. I bought a Xolo Q800 and it comes with a "Xolo Care" app installed. This app gives you their contact details and a toll free number you can call. I've read that when you contact them, they come to your house to collect the phone and give you some receipts. Then they contact you again once they've fixed your handset.
You can also find the same contact information on their website.
