I downloaded the deployed model from Azure Portal and I was trying to modify some measures and redeploy the solution. Everything is greyed out and I can change nothing, even when I want to save the model I get the following error (see picture below): Click here
Thanks in advance!
Sharing the answer as per the original poster on the Microsoft Q&A platform.
The problem was fixed by itself I kept closing and reopening Visual Studio until it allowed me to process the cube and re allowed me to modify my measures.