Zudio - Exchange not possible due to alleged server issue

I bought many items from Zudio Kolkata *days back, * of my son’s pant needed exchange due to size misfit. I visited Zudio Asansol, WB which is situated at least *.*-*hrs drive distance from my place, leaving my hospital duties being a doctor, not to mention the time energy & of course the petrol for the car. While entering the store the billing counter person was reluctant for exchange knowing that items were purchased from kolkata, however on requesting, told me that they had server issue then, but we should continue with our shopping and later the exchange ll be possible.
Even after spending close to * hours in the store still we were denied exchange in that store citing server issues although regular billing for all customer were going on smoothly. I do have the video footage of our talk with Mr Mukherjee who claimed to be the one in charge, he refused to share any contact number or email to escalate the matter / raise a complaint.