How to update data on data extension using AMPscript?

Question

I need help with updating existing data in a data extension. When a user clicks on an email link to change their status, I need it to be changed in the data extension. For example, if user A has status X , when he clicks the button , they need to be updated to status Y. I need to do it in AMPscript. Can you help me with this?

This is the code I've written so far:

%%[
  var @reservationid, @hotel_name, @city, @country, @fromdate, @todate, @value, @customerid,@reservationstatus
  set @reservationid = RequestParameter("reservationid")
  set @reservationstatus = RequestParameter("reservationstatus")
  set @customerid = RequestParameter("customerid")
  set @hotel_name = RequestParameter("hotel_name")
  set @city = RequestParameter("city")
  set @country = RequestParameter("country")
  set @value = RequestParameter("value")
  set @fromdate = RequestParameter("fromdate")
  set @todate = RequestParameter("todate")
  set @salutation = RequestParameter("salutation")
  set @firstname = RequestParameter("firstname")
  set @lastname = RequestParameter("lastname")
  
  

  Var @Submit
  Set @Submit = RequestParameter('submitted')
  If @Submit == 'submitted' Then
    UpsertDE('Final_Task_Table',1,'reservationid',@reservationid,'reservationstatus', 'cancelled')
  Endif
  
  
  ]%%

Answer 1

UpsertDE function only works in email send context. Use UpsertData to add or insert rows into a Data Extension in a Cloudpage.

Try to change the UpsertDE line to this:

UpsertData('Final_Task_Table',1,'reservationid',@reservationid,'reservationstatus', 'cancelled')