DexCom Sales Reps

sales rep doesn't want to file on my medicare avantage plan; why? wouldn't the sales reps know that there are existing appeals recommendations to battle these problems? this rep is insistent that the best way is for me to pay out of pocket and pay out of pocket for future supplies. just thought i would ask if you might have any clue why the rep would feel this is best. my plan is designed for specific chronic health problems; i think i could eventually get them to come around if they don't approve it the first time. the insurance tells me they cannot tell me anything about coverage unless a claim is first filed. i am confused. thanks for your help.