Wiper has come loose and does not work. Needs realigning.

Pop off the cover at the pivot and you will see a 10, 12, or 14mm nut.
Have the wipers in the park position. Tighten that nut when the wiper is even with the other one.

Yes I agree. Adjust the rest position of the wipers if the adjusting nut is loose. If it's a wiper relay then it was only 15.15 from the dealer.