Only thing I can come up with since we are unable to inspect the gun is the firing pin has punched through the primer and become wedged in the primer pocket flash hole or the hammer has sheared the half cock or full cock notch and become wedged up in the slide recess, if this is the case, you may be able to insert a brass or nylon wedge into the rear of the slide to manipulate the hammer down into the frame while having a helper push back on the slide to free it.
If the firing pin is wedged, the retainer pins will be blocked by the frame so you may have to use a solid brass rod inserted down the barrel and into the expended case, be sure to use a rod smaller than 9mm/.38 to keep it from becoming wedged in the expended case,,, whack on the rod while keeping the barrel pulled forward and this should drive the slide back and access the ejection port.
Be sure to restrain the front of the barrel in a well padded vice when you do this to prevent battering or shearing the barrel lugs.
If you get this far, you should be able to lever the case off the firing pin.HTH