I had this after I hit a partridge full on. The impact knocked the square sensor block from it’s mounting. My dealer managed to refit it so that it looked correct, but the system had to be realigned, apparently. That, I was told, involves 4 hours on a rolling road and cost just under £500! Safety related, so what do you do? This system could save you and your passengers lives, or that of a wayward pedestrian. They have you between a rock and a hard place! Hopefully, the new position, behind the badge on the 7.5, is more robust.
Good luck with fixing it, but I think this may be a dealer cash cow that is hard to avoid.