Sermon Documents not scrolling till I change font size

TCBlack

I'm running Logos on an Amazon Kindle Fire.  Yes it is completely up to date.

The last two Sunday's I have been preaching and suddenly my open sermon document would not scroll.  While preaching I had to go into the display settings, decrease the font size and then I could scroll a bit farther.

This is in a church without internet access.  It almost acts like it needs to download the rest of the document, but the rest of the doc is there, I just can't see it till I decrease the font size.