Progress Bar in a lesson only goes up

create a lesson within a course enable progress bar on lesson setting add some contents and questions. login as student and attempt the lesson make sure progress bar doesn't keep increasing for the same page. Note: the progress bar is determined by attempted/visited page (this includes correct/wrong attempt for the question). If the current progress bar is displaying 50% (assuming the student is in the middle progress of a lesson) and the student re-visited the first page again, the progress bar won't be reset to 10% but it will display the current progress which is 50%.