Quest Diagnostics review: Billing

I go to Quest Diagnostics in Ct at 135 Storrs Rd. Mansfield, Ct. Yet they consistently send the claims to Illinois and my insurance then denies it because I am not covered in Illinois, which should not be a problem, since I did not get it done in CT. I even tried to correct it last time I got my lab work done, in person and they deny they are doing it and blame Anthem. It's a drama that never ends. The two companies clearly do not talk to each other in any way shape or form. Both are claiming the other is wrong. Quest claims they are billing to RI where the Dr. is, but the lab is done in CT where the home plan is and they say Anthem tells them to do this, yet Anthem says they are billing to Chicago, and of course they refuse to talk to each other.