I had this exact same problem, I did exactly as above
- remove the rubber thing that goes along next to the wipers,
- take wiper-covers off,
- remove wiper bolts with wrench
- take wipers of
- then take the plastic panel off.
I found the ball joint had worn away on the arm so it kept popping of, I put some plastic bag over the ball joint and reattached it. I also put an elastic band on the arm to keep upwards pressure on the ball joint. The plastic made it a better and tighter fit and will keep the wiper in place.
I hope this helps mate
