id definition 1 Proof of Eligibility Unknown or Unavailable 2 Litigation 3 Authorization Delays 4 Delay in Certifying Provider 5 Delay in Supplying Billing Forms 6 Delay in Delivery of Custom-made Appliances 7 Third Party Processing Delay 8 Delay in Eligibility Determination 9 Original Claim Rejected or Denied Due to a Reason Unrelated to the Billing Limitation Rules 10 Administration Delay in the Prior Approval Process 11 Other 15 Natural Disaster 16 Lack of Information 17 No response to initial request