Hi,
Thank you for sharing your issue. Could you please try the solution below:
- take a full backup of your project just in case of mistakes
- stop Katalon Studio
- delete .project file
- delete .classpath file
- delete /bin directory as well
- delete /Libs directory as well
- delete /.cache directory as well
- restart Katalon Studio, open the project
Let me know if it works/ does not work. Thank you!