i need help agin....

class Student {
    constructor(gpa, credits){
        this.gpa = gpa;
        this.credits = credits;
    }

    stringGPA() {
        return this.gpa.toString();
    }

    get level() {
        if (this.credits > 90 ) {
            return 'Senior';
        } else if (this.credits > 60) {
            return 'Junior';
        } else if (this.credits > 30) {
            return 'Sophomore';
        } else {
            return 'Freshman';
        }
    }
  set major(major){
    this._major=major;
    const level=this.level;
  if(level==="Senior" || level==="Junior"){
this._major=major;
    }else if(level==="Freshman" || level==="Sophmore"){
this._major="None";
    }
  }
}

var student = new Student(3.9, 60);