this.reactiveForm.get("firstname").valueChanges.subscribe(selectedValue => {
  console.log('firstname value changed')
  console.log(selectedValue)
  console.log(this.reactiveForm.get("firstname").value)
  console.log(this.reactiveForm.value)    //shows the old first name
      
  setTimeout(() => {
    console.log(this.reactiveForm.value)   //shows the latest first name
  })
     
})