Ob doctors office sucks

I’m 14 weeks and I’m requesting the nipt test and the nurse keeps insisting that I don’t need it . I keep insisting for the test and they don’t want to do it .. any suggestions on what I can do in this situation? I only had one ultrasound at 6?weeks pregnant

***I have hypothyroidism and gestational diabetes and my genetic dr said that my ongyn needs to order the test. I even offer to pay cash for it..