The person who owns the land contract dies and there is no will, what happens to the contract?

Will or no will, the decedent's next of kin would inherit according to your state's intestacy laws. You should contact the probate court to determine if a probate case has been filed.

If so, you have a contract with the probate estate.

If not, you might have to nudge the heirs to step up to the plate. Suggest to them that you might have to bring an action against them to quiet title.