Firebase observe creates duplicates while appending

Hi there! I'm currently trying to observe values from firebase RTDB, but every time the values of the children change, the swift app creates a duplicate item with the info, while the value in the app doesn't change.

My functions to observe the values:

     
    var job = JobData()
    let _commentsRef = self.ref.child("jobposts")
     
    _commentsRef.observe(.value) { snapshot in
       
      for child in snapshot.children {
         
        print (child)
         
        let snap = child as! DataSnapshot
        let dict = snap.value as? [String: AnyObject]
        job.id = dict!["id"] as? String ?? "id"
        job.title = dict!["title"] as? String ?? "title"
        job.company = dict!["company"] as? String ?? "company"
        job.city = dict!["city"] as? String ?? "city"
        job.salary = dict!["salary"] as? String ?? "salary"
        job.creator = dict!["creator"] as? String ?? "creator"
         
        print(job)
        print("JOB TITLE: " + job.title!)
         
        self.jobs.append(job)
         
      }
    }
  }

The view:

      ScrollView {
        VStack(spacing: 20){
          ForEach(session.jobs) { job in
            JobCardTemplate(job: job, session: self.session)
          }
        }
        .padding()
      }
      .navigationBarHidden(true)
      .navigationBarTitle(Text("Darbo Pasiūlymai"))
    }

Anyone might know why this is happening? Thanks in advance!