Project Targets went negative!

I just noticed my target was -511, so I clicked reset and it went to -900…
See attached.

I am pretty sure I didn’t delete any words, let alone 511~900 of them.
Closing and re-opening it set the number back to 0. But that is to be expected.

I’ve been getting this a lot too, but only recently and, as far as I can tell, only on one project. (But I don’t typically change projects when I’m in the middle of one.) I also have to close and reopen the project to make it go back to normal.