Did you buy this tire replacement contract from your selling dealer or a tire place? Either one you should take the tire/rim to them and file a claim. They will have to inspect the tire/rim and determine if its covered or not.
NOTE: I deal with a similar contract for our customers at the dealership, I have to call the company and file a claim on behalf of the customer. Sometimes they will send a person to inspect the tire, sometimes they just ok the replacement and give an authorization # to replace the tire including mount and balance. I have not filed a claim for vent rims on behalf of the customer yet. Read the particulars of your tire replacement contract and bring it with you when you file a claim.