Giant PDFs exported from notes

Hello. I've been using the Tab X for school work and am very impressed with it. Makes my life way easier for math work, and the size is perfect for university.

I do a lot of hand-written notes which get auto-saved to PDFs when I exit the note-taking application. I then connect to boox drop and download them for submission to school.

Erverything works great, except sometimes the PDFs are giant. For example, I expect 8.5x11, and I got 22.92 x 30.56 inches. What are these sizes??? It take a few extra steps to convert this to 8.5x11. Is there any setting I need to change to fix this automatically? Also, in case anyone knows, it would be amazing to automatically save as greyscale instead of color.

In case this matters: I always use the "Horizontal Line 30" template.

Thanks in advance!