171 - Other insurance coverage information (health, liability, auto, etc.).

The payer is rejecting this claim because you have indicated (on the insurance card in Therabill) that the payer is not the patient's primary insurance (i.e. they are secondary).  However, information is missing about primary insurance.  This can be caused by the following.

• You do not have an active (unarchived) primary insurance card for the patient in Therabill.  In this case, make sure you go to the edit client form and add a primary insurance card.  Make sure you send the claim to primary insurance prior to submitting it to secondary (as secondary needs to know the adjudication results from primary).
• You did not enter payments/adjustments from primary insurance into Therabill.  Make sure you enter all payments and adjustments that you received on your EOB from primary insurance.