Hi,
Suddenly, I can no longer change the top offset units of an element. In other words, I can’t change from pixels to vh or % and vice versa.
I restarted my computer and cleaned out my cache. I am still having the issue. 
Hey @rootsofamerica1776 ,
Do you have a link to the site you’re working on? If not, have you reached out to the customer care support team to take a look.
I’ve gotten around this issue by typing (for example) 12.5vh instead of pressing the buttons which are broken.
may we ask for the video of sitelink with this problem (if pressing the buttons is not working) in case of privacy reasons it won’t be possible, please use the link Roberto shared in this thread.
I’ve done the same and I tend to do that as it’s faster for my workflow by typing in the measurement in the inspector.