The prediction of future weight seems to be broken

elephant_in_the_room

I have logged just over 1200 calories for the day. When I click on 'finish the day', I get told that if every day were like today, I would weigh 262 kg in 5 weeks. That's 190 kg more than I weigh now, and I don't think it's physically possible for my liver to work that hard to make me gain 190 kg in 5 weeks, surely not on 1200cal/day.
I got a similarly unlikely result yesterday when I had logged altogether a bit over 1800cal.
What's going on?