Built a new house. Hickory floors with Jacobean stain. Semi gloss poly (I think).
We moved in recently and I noticed when something has spilled and I clean it up stain lifts up on the paper towel. I would have thought the poly would seal the stain in, but I really have no idea so thought I’d ask.

Did you have a contract with the Builder, or just with the ''realtor/Seller"?
You will have trouble caring for your floor without knowing what was used for the finish. The Builder will know who finished the floors. Your realtor should help with contacting the Builder to find what finish was used.

I will get in contact with the builder today. Should the stain be coming off on a paper towel. You can’t see a difference on the floor just coloring of the paper towel.

May be colored wax over the finish