@313! That is how the stock seat is. It won't get any better even after some time is passed. You can get another brand new seat, and it will also get hard in roughly 2 months.
If its too much problem for you, then you can go to Poshish (Seat Cover) Makers and ask them to double/tripple the foam, to make it comfortable. It won't help a lot, but it will create a little difference.