Excel 365 running extremely slow

I just installed Microsoft 365 and was using Office 2012 before on my Windows 10 desktop. I installed Microsoft 365 on my work network and now have taking my computer home because of quarantine. At work Excel is working great but from home it is taking a very long time just to open a blank sheet and once open it takes a very long time to move into a new cell or to just type a character. Status information at the top of the window says Excel Not Responding.  I opened Excel in safe mode and have the exact same experience. I moved the default printer from a work printer to Microsoft PDF.  The rest of the Microsoft 365 suite opens and works fine, for example, Word and PowerPoint.

Any ideas of what may be happening with Excel?

Thank you for your help.