Hello,
Thank you so much for taking the time to reply.
Yes, it was happening in all Office applications.
Office 2016 was downloaded on my device in 2018 and I've been using it since then.
I use a PC, Windows 11.
I found out the problem. I had to keep doing a quick repair for Office 2016 applications. Since I had to keep repeating this, I tried the more extended repair on-line. After this I received messages to activate MS Office 365 which I did not want. However, I also noticed in Programs, that Office 2016 said it was now installed today, not in 2018. So, when I clicked on "activate", instead of going through with the unwanted subscription, it did give me an option to enter a product key. I entered the product key I had for Office 2016 and that fixed everything.
I believe that the on-line repair must have uninstalled, then reinstalled Office 2016 which is why it then needed a product key.
Again, thank you for your time in answering my question. I greatly appreciate it!