Please guide to install the latest 1.2.0 version while the previous version has been already installed in Matlab.
The recommended procedure is to uninstall v1.1 and then install v1.2.
In order to uninstall previous version, you'll need to open the matlab version on which you installed the 1.1 version and go to Add Ons -> Manage Add Ons:
Press those three dots and choose uninstall.
Then you can install v1.2