Hello and thank you for your question!

Memory foam is a polyurethane-based foam that does soften up with use. The floor sample you tried at the retail location has been exposed to regular wear, while the new one you just got was probably just manufactured and will soften over time.

However, I would check the "law" tag on the head of the mattress. It provides the manufacturing date & other information, along with the product name. Make sure you received the correct product.

Thank you again and have a nice day!

You can walk on your bed for 20 minutes and this will help to break open and soft the mattress up.

First of all I have noted inconsistencies from time to time with memory foam. Second the memory foam in the store is adjusted to the tempurature of the store. Firmness of memory foam goes up with the colder the surrounding air. Having said this, it can take a day or two for the new mattress to adjust to your new homes temperature. Also if you keep your home on the colder side the mattress will remain firmer. I would monitor the mattress over a week or so and see if you notice any changes.

It will definitely soften the more you sleep on it.