DISCOVERY's APP has incorrect information - APPAULING SERVICE!!!!!

So I searched for a doctor on the DISCOVERY APP, and found a list of doctors in my network and chose one and went in for a consultation.

I then paid cash , and then sent the claim to discovery, only to be told that the doctor is not in their network any more... HOW? Discovery says that the doctor exited the network and didn't notify them, so that's why they are still on the list... BUT WAIT? whose fault is it then, because, they (Discovery) is responsible for maintaining the infor available on the app.

I'm highly disappointed in the service I got, because this is not fair. AND ON TOP of it all, I have been referred to a specialist, and they have advised that they will not pay for it, because, I was referred by a non-network doctor - so now I have to go to yet another doctor to get a referral letter! WOW... Totally unacceptable!