"Lost" paperwork

Help! I have been given my surgery date, 6/11. But I still do not have approval from my insurance company. They still say they have not received any paperwork from my surgeon's office. I have spoken to my doctor's office and they assure me it has all been sent over. The ladies at my doctor's office are starting to get very short with me ( I am calling so much) but I can't get through the approval process if my paperwork is never reviewed! I am afraid that my date will come and go and without approval, I will get pushed back. Any advice on how to be pleasantly persistant with the Dr's office without them getting mad at me?