Git (bitbucket)- Can't revert commits from Katalon Studio or Bitbucket

I don’t know how to Undo or Revert merged commits as there is some important files and data i found them disappeared and deleted.
so anyone can help please how to Undo this commit

See the “Show History” section here: https://docs.katalon.com/katalon-studio/docs/git-integration.html

Right click on any commit, a list of menu options will display.