Brake service suddenly 14tkm earlier?

After I got back my red from the service yesterday, he now shows me today that the brake service (back) is due in 1800km. But what can’t be because the interval before the service was still at 16,000km. I have recorded the service times extra because I wanted to know if something changes because of possible UpDates. He did not get an indication of the NL. Only the usual data were read out. So how can it be that the service display from one day to the next the other about 14tkm “swallowed”? And also the question if I can reset it myself? I really don’t want to drive to the NL again because of such a “bollock”…