Hidden piano roll

The lower part of my piano roll is hidden. I can’t scroll all the way down to the lowest note, and the vertical zoom is gone. I can click on the piano and drag it all the way down, out of the picture, and it will make a sound. Am I the only one with this bug (I assume it’s a bug), I’ve tried googling and haven’t come up with anything? I’ve tried doing a factory reset.

Win? Mac? Screen resolution? Graphics hardware?

Windows 10. 1920 x 1080. NVIDIA GeForce GTX 1660

I’ve resolved this issue now. In the toolbar I selected Set up window layout and crossed off controlled lanes (it was on). The entire piano roll is now visible, along with the scroll and vertical zoom.