No light on farm [Vanilla 1.12]

• I was working on my farm and the crops were taking much longer than usual, and when i went to check the light level I realized the farmland had a light level of zero!

Originally this was an underground farm, so I checked and I was having the same issue above ground. In multiple saves and in realms.

The area was lit properly, the squares just outside the farm having a light level of 11-15. I'm not sure what the issue is, and I couldn't find a report of anyone else having the same issue.

I've attached my F3 screenshots showing the light levels.