Lube the pivot points on your wiper arm with silicon grease... Worked for me. Both the lower arm joint and where the blade sits in the arm.

 

Remove the wiper blade from the bad wiper arm, stick a large round cylinder (coffee mug container?) under the middle of the wiper arm and bend the arm downward but not too hard. This adds more tension to the tip of the wiper arm.
Install the wiper blade and try it out.