Hi,
Problem is solved. I explain how it was solved.
With du -sh * . I saw that /home was using more of the space. Running the command recursively inside Home, i found that the folder .cache/bazel was 3.3G , I moved this folder to my mounted SSD and GUI is loading properly now.
So , now the remaining thing would be to configure Bazel to cache files in a non-default folder directory, inside the mounted SSD.
Thanks for your overall help on this post, I appreciate :)