Why is BCBS denying Carelon Authorizations?

I am in charge of Authorizations for my facility and have recently had an influx of denials for Authorizations being absent. When I call BCBS to inquire about this denial reason, after waiting almost an hour and most likely getting hung up on before I even get to speak with someone, they inform me the denial reason is because the Carelon authorization is for a rental and not a purchase. I've spoken with Carelon myself to ask if there is a difference between an Authorization for rental and/or purchase and they never know what I'm even referring to and the date range is based on the member's compliance for the first 90 days. I feel it is unfair to these Patient's who pay hundreds of dollars each year for premiums and I'm fighting tooth and nail over the phone to get these adjusted but have to call 3 or 4 times before I get  an Agent who will sent it back for adjustment. I will also have to call multiple times on a single claim because a Rep will tell me they'll send it back for reprocessing but they never do. 

Is this normal for other facilities or can a representative verify this with documents supporting this?