When Clicking a Cell, Excel Jumps to a Different Cell and Highlights All Cells in Between

I have Excel LTSC Pro 2021, and just in the last 2-3 weeks, this issue has appeared.  It's EXTREMELY annoying!

I select a cell and then without warning, Excel jumps about 300 cells higher and highlights all the cells in that column between the cell I was looking at and the new top of the selection.

I've wasted enough time Googling for an answer as to why with no joy.  I'm not sure if related to a major Windows/Office update or not. 

Thanks to any/all who can point me to whatever setting or Registry fix to stop this extremely annoying behavior in Excel -- which I use almost every day of the week (I'm a CFO...go figure!  LOL).