Final answer:
If a claim is wrongly denied, the biller should appeal the claim with the necessary documentation to prove its validity. Writing it off or balance billing the patient are inappropriate actions.
Step-by-step explanation:
If a claim is denied, investigated, and found to be denied in error, the biller should appeal the claim. This involves contacting the insurance company and submitting all necessary documentation to prove that the claim is valid and should be paid. Writing the claim off or balance billing the patient are not appropriate actions in this situation, as they would lead to a financial loss for the healthcare provider or an unfair charge to the patient. Refiling the claim may be an option, but it is important to first resolve the issue that caused the initial denial to prevent the same error from recurring.