There is an on site parking assistant, who would be helpful for you, and you can also find the contact information on google. I hope you find your placard soon!!!
Contact either the parking attendees or the stores in that immediate parking area someone may have turned in the placard, much luck to you.
Contact security person
Contact security
No phone number you will have to back and ask. Or get a replacement.
There is a parking lot opposite of McDonald's where you may find parking for a fee maybe someone turned in your place card there.
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