Reliance Trends — manufacturing defect in clothes

Address:

ansal plaza palam vihar, Gurgaon, Haryana, 122001

Bought clothes from reliance trends ansal mall gurgaon. Clothes left color after first washing. Not only this atual clothes, this runined other clothes washed along with that one.
On 24th feb went to store for exchange... Their response was due to server issue they can not generate bills and exchange. They requested me to come in weekdays.
On 26th feb, visited again and after waiting a while, they denied again for exchange saying due to delay in reporting issue.

They could have said the same thing on 24th when it was not possible. Why did they ask the customer to come back