Hi George,
I am also having this problem; it came out of nowhere yesterday. I don't believe I updated Word (though perhaps it was updated automatically); and I did not update or change anything else prior to the problem's emergence.
As was said above, the problem is that, upon zooming in using the trackpad, often, I will be thrown upwards to a completely different and distant page in the doc. (So far, I have only been moved up in the doc, not down.) This makes editing and maneuvering extremely difficult. Note also that, as of yesterday, when I zoom in using the trackpad, even if it doesn't throw me to some different page, it will at least throw me to the far lefthand side of the paragraph I am zooming in on. That is, it doesn't zoom in on where my cursor is, or what's in the centre of the space that I am zooming in on; it throws me suddenly to the far lefthand side, if it doesn't throw me upwards to a completely new location.
I have ensured the issue is not my trackpad: in other editing software, on webpages, on pdfs, nothing close to this problem occurs; I go where I mean to; I'm thrown nowhere.
The problem seems not to occur when manually clicking on the little "+" zoom icon in Print Layout. Zooming in via click doesn't throw me to the lefthand side of the para either. It zooms in on where my cursor is, which I think is how it's supposed to be.
I have tried the other view settings. I don't ever use them, so I am unsure what is standard. But in a number of settings, what seems to me like a version of the problem recurs. For example, in draft, when I zoom in or out, I can't help but move upwards. This is true even when clicking on the little "+" or "-" buttons instead of using my trackpad. No matter where my cursor is, if I zoom, I go upward, and soon hit the very top left of the doc. But again, not sure what's standard here. I always use the print layout.
This issue isn't doc specific. It came out of nowhere, seemingly, and now it plagues all my word docs.
An interesting new problem that came about simultaneously is that, when using the "Read Aloud" feature, if I pause, it now sometimes keeps speaking. But it doesn't say what's next in the doc. It instead circles back to something it already said, or somewhere even earlier in the doc. It speaks even though it is not highlighting the words it's speaking, so I sometimes have no clue what it's reading. Turning off the feature, rather than simply pausing it, shuts it up. Again, this problem came about simultaneously.
To try to remedy all this, I have updated my mac from what I think was high sierra to catalina. (My mac is a macbook, 15inch, mid or late 2015 model.) I have uninstalled and trashed my Microsoft office and its caches etc, and reinstalled them fresh. I have also tried the 4 strategies recommended in the above post. Nothing has helped.
... Except for one thing. I was able to download a much older version of word for Mac OS 10.11-2 (or somewhere around there). I haven't kept it, since it was without some of the features I value. But as far I could tell, the problem didn't recur. It would zoom in where I wished, as had been the case on the more updated word until yesterday; it wouldn't jump left or anywhere else. But I would prefer to have a fix that didn't require downgrading my software!
Please let us know what can be done. As mentioned, this particular problem makes editing and maneuvering extremely difficult.
Owen