Please check the 4 bolts on each side of the mazda towbar.
On my 2013 BT 50 I discovered after unhitching my 2.8 tonne van that the tow bar was loose. Of the 4 nuts and bolts on each side two had come undone and fallen out each of the 3 other bolts on each side were loose and about to fall off.
By a coincidence the fellow next me in the caravan park also had the same problem 12 months ago on his BT50. Lucky he had a few spare bolts from his repairs. Of note was that were no spring washers under the nuts and they were not nylock nuts.