My insurance claim denied by oral surgeon because it is HMO plan instead of PPO plan. I have lost $500 because?

My insurance claim denied by oral surgeon because it is HMO plan instead of PPO plan. I have lost $500 because of it. Is there any way that I can get my money back? They never told me where to go, the insurance company, SafeGuard, told me I can go any oral surgeon because there's no oral surgeon who is on their providers list nearby me. I rechecked with almost 3 people of customer service of the SafeGuard. So I went to the oral surgeon nearby me and they only told me to submit the claim form to insurance after the surgery and my claim was denied because they are not accepting any HMO dental plan. I feel like I wanna sue them because I am poor and I feel like I was misinformed. Is there any way I can receive the benefit from my insurance for the surgery?