You seem to be having some difficulty. Hope this helps.
Section. 10.
No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility.
When you get a chance, please let me know if this includes the portion you feel proves your claim.
If you can’t read plain English I doubt that my input would help. Read the Federalist Papers (you haven’t done that?) to discover what the Constitution means.