Wheat issue

I seem to be running into an issue. my farms will only harvest from certain placed fields and not all. even when they have no wheat.

I had two farms and four fields next to each other, two fields were depleted and two were still showing 200 wheat. The farms had the exclamation saying it needed the wheat but wouldn't harvest from the other fields. I demolished and replaced the fields and they harvested them. I had settlers working, spare ones too. I got lots of unemployed lol.

You could use several farms for only one wheatfield... So, a farm does not use more than one wheatfield at the same time.:)