Yes, Layla mattresses require a four-week break-in period to adjust to your body weight and shape.
If you’re not satisfied with your new mattress, you can return it after four weeks—but no later than 120 days from the date of purchase.

Most mattress brands have a similar policy. Generally, it takes anywhere between 30 and 60 days to break in a new mattress (except for latex foam mattresses, which have a 2- to 14-day break-in period).