Sleepwell — duet luxury dual comfort mattress

Address:

H.no : 843, Sector :38A, Chandigarh, Chandigarh, 160036

I purchased this mattress in nov 2015 and suddenly it has started bulging from the center, it started with a small bulge but has increased three times it starting size in just 2 days... Please advise what needs to be done. I am in chandigarh please provide a visit from the concerned person to understand the actual concern. We have purchased more than 4 sets of mattresses but am facing problem only in 1 please do the needful.