My passenger back side door won't open. How do I get it to open ? on 2005 Kia Spectra

MY passenger back side door closed one day and now won't open. We have tried locking and unlocking and pushing on it. Can NOT get it to open any more.
Dealerships REFUSE to fix it. Auto repairs want a fortune to take door off and 'see' if it's fixable.

Asked by for the 2005 Kia Spectra