Same problem happened to my
Same problem happened to my 2016 ram 2500 I called customer service at Chrysler (had a very nice representative) Chrysler knows now after three months of investigating what the problem is (module in the locking mechanism in your tailgate is faulty) it’s not your fault the tailgate came open and got damaged so Chrysler covered all costs (repair and body shop) no problem since work was done in August 2017
Thank You and have a great day - Dave