Why is only the last object written to the HashMap?

Question

Java

Hello. I read data from the file, then in a loop I create an object and add an object with a unique key. For some reason, it is added, but in the next iteration, the hashmap is reset and the current object is added. Why is that? The object has hashCode and equals implemented.
The code has been truncated.

HashMap<String, User> map = new  HashMap<String, User>();
  while ((line = reader.readLine()) != null) {
          
          scanner = new Scanner(line);
          scanner.useDelimiter(",");
                 User user = new User();
          if (index_str != 0) {
            
            while(scanner.hasNext()) {
              
              String data = scanner.next();
              
              if (index == 0) {
                      user.setTableId(Long.parseLong(data));
              } else if (index == 2) {
                user.setLastName(data);
              } else if (index == 3) {
                user.setName(data);
              } else if (index == 4) {
                user.setMiddleName(data);
              } 
              index++;
              
            }
            
              String key = user.getKey();
              System.out.println(user.getKey().hashCode());
              map.put(key,user);
            

            index = 0;
          }

          index_str++;
        }

Answer 1

...I create an object and add an object with a unique key.
The object has hashCode and equals implemented , but I will add the user.getKey() key to the map.
Is there anything wrong here?