Where I live you give a copy of your DNR to doc, hospital and keep the 3rd on your fridge. You also get a small one for your wallet. If paramedics ignore your DNR you can sue. I have one from my doc due to my emphysema and not wanting to stick around should my lungs fail again. I was going ot put my DNR in the hotel on a table so they knew dont touch me. They cannot perform CPR on me. Now if I am out of my county where it isn't recorded than they wont know unless look in wallett like in an accident
Good for you, though I highly doubt it is the case.
When they arrive they're required to ask permission to assist you.
If you're unconscious consent is implied.
Expecting/requiring first responders to go through your wallet/belongings to ascertain whether or not you have a valid DNR in an emergency situation is a danger to the public.
While you may sue them if you're so inclined, you more than likely will be wasting everyone's time and resources in doing so and will likely lose. I'm curious to see that tested in court.
On the other hand if you're conscious when they arrive and clearly state that you refuse their help they -in theory- can't touch you. That would be assault.