I'd try a squirt of WD-40 into the female buckle and give it a try.
Insure the male end is not bent/twisted.
Compare the innards of the female with the passenger side buckle. Anything different or missing?
If you are still getting nowhere, I'd remove the female end off of the floor. Take it out into the driveway, slap it around with your other hand/ push the button, more slapping! With a bright light see if you see anything tucked in there. A penny, dime, or etc. May still be hiding in there.
Return with good news!
Thursday, February 14th, 2019 AT 5:27 PM