Pages Snafu (add a row and pages goes bonkers)

This past week, I tried to add a row (either above or below an existing row) in a Pages document.

The attached screenshot reveals what happened when I tried to do that. All of my lines of text have vanished and replaced by blank information that is rather baffling.

I have no clue on why this is happening.

How can I fix this?

Thanks in advance!

Chris