My claim in January has been denied after I cancelled my coverage in April. How can I get the claim covered?

My claim in January has been denied after our company cancelled my coverage in April.  How can I get the claim covered?  My son Ty Green went to Urgent Care on January 29th, 2024.  Paid his $35 copay and received treatment for a respiratory infection.  The claim was turned in on January 31st from the provider. The provider states that the claim was denied on September 12th, 2024, almost 8 months later. They inquired again on September 21st, and BCBSOK applied the remaining amount due as his deductible on September 26th.  In the past URGENT Care has been covered on this policy, please advise why the coverage has been denied now. Policy 307762, VOK07762