Dragging query not sorted

My husband had an operation on 7Jun2023. This has been pre-authorized. For reasons beyond my understanding, between the vendor and Momentum, one procedure code is not being paid. 1. If this auth was given the go-ahead from Momentum before the procedure, why would this one code now not be paid? 2. If the vendor made an error in the procedure codes, why are we being penalised? i am not a surgeon and it is not the patient's responsibility to check the surgeon's work. 3. Why can we not get a straight answer to this non-payment? Every time i call, i get a different line and another escalation and another please follow up again later. 4. Why does it take 5 months to get answers to a simple, pre-authed transaction??? Very disappointed in the system.