Properties Tab/Ribbon not working

Hi all!

I am having issues changing the properties of a line/object through the properties tab and ribbon. 

I havent had a problem before, but when i select something and try to change colour/line type etc, nothing happens. The command line just reverts back to "command:"

If I use the Ctrl+1 pop up, i can change properties. Though this solves the problem, it isn't as convenient as having the tab or ribbon in the border 

No layers are locked/frozen etc, and all i can think of is that i've accidentally typed in a command that has altered something. I am having the problem in all cad drawings. And the problem doesnt occur when i use a colleagues computer.

I am only 6 months into using Autocad, so if this is a simple problem, apologies Image may be NSFW.
Clik here to view.

Thanks

Joe

Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.Image may be NSFW.
Clik here to view.

Image may be NSFW.
Clik here to view.