MonoDevelop not loading solution

After having troubles with unity hub and launching unity 2019 and unity 2017 I deleted unity 2017.

The ** Problem: ** Unity 2019 is giving me the following errors and MonoDevelop is not loading the complete solution of the project when double-clicking on the c# file.
And after the c# file opens the script highlights functions as if there is an error in building the solution.

Then I faced this problem maybe because I took the MonoDevelop Application in and out from the application’s folder so …
I think that references to MonoDevelop were misinterpreted.

Note: I have a Macintosh

I would appreciate any help.

At last, I deleted MonoDevelop and I am going to re-install it maybe that will fix the problem.

I ran into that issue a while ago, I just did a clean install of Unity aking with MonoDevelop again.