Emergency Physicians at Porter Hosp. PC Inaccurate billing and refusal to refund overpayment Oklahoma City Oklahoma

Received services on 12/01/2013, insurance paid on 1/29/2014.  I also paid in error on 2/10/2014.  I received confirmation via benefits statement that my insurance paid on 1/29/2014.  Emergency Physicians at Porter Hospital P.C. has stated they did not receive the insurance payment and refuses to refund my payment.  I have provided proof of payment on three occasions and still no resolution.  Each time I speak with someone at Emergency Physicians at Porter Hospital P.C. I am told something different.  On March 26, 2014 I was told my account was locked and information could not be provided....Really?!