Sagging Picanto mattress in less than two weeks.

I bought sealy Pincanto queen mattress at Sky City sleepmasters and it was delivered beginning of this month (july). After 2 weeks my daughter asked me do I notice that the mattress is now bit saggy. I could not take her serious. Now the mattress is literally sagging as if is being used for 10 years and feels so uncomfortable. I contacted the sales lady at sleepmaster and she said she will log a complaint on my behalf. I am literally shocked that this mattress is a sealy, I grew up sleeping on sealy bed and never experienced such low quality from the brand. What happened to Sealy quality?