Anytime Fitness

My son had a membership for a year. Last December 2019 he cancelled his membership with proof of Military contract, which supersedes contracts like leases and gym memberships. I also followed up with the gym by phone on March 10 to be sure it was cancelled and not suspended temporarily.
He is now serving overseas and today a bill came from their collection agency.
Way to go ruining the credit of a young man while serving his country. He had not gone to the gym since cancelling when he enlisted.