"You are saving a DNG Recipe file (DCPR). Use Export and save the camera profile to the User Camera Profile folder.
Windows—C: \ Users \ [your username] \ AppData \ Roaming \ Adobe \ CameraRaw \ CameraProfiles \
Mac—Macintosh HD / Users / [your username] / Library / Application Support / Adobe / CameraRaw / CameraProfiles / "
Which worked for me. I was using ""save recipe as", which was why I was getting the dcpr extension.
Many thanks !!