why is when i do put request using django rest framework i got 200 but when i try to see one of fields it shows null using get request not the put one

[galomari]

i was trying to do put request on postman and its scussec but when i try the get method to get same result one of the fields which's car_ year shows null`

viwes.py

from django.shortcuts import render
from django.http import HttpResponse,JsonResponse
from rest_framework.parsers import JSONParser
from .models import Driver
from .serializers import DriverSerializer
from django.views.decorators.csrf import csrf_exempt
from rest_framework.decorators import api_view
from rest_framework.response import Response
from rest_framework import status
from rest_framework import generics
from rest_framework import mixins

from rest_framework.views import APIView

Create your views here.

class GenericAPIView(generics.GenericAPIView,mixins.ListModelMixin,mixins.CreateModelMixin,mixins.UpdateModelMixin,mixins.RetrieveModelMixin,mixins.DestroyModelMixin):
serializer_class = DriverSerializer
queryset = Driver.objects.all()

lookup_field = 'id'

def get(self,request,id=None):
    if id:
        return  self.retrieve(request)
    else:
        return self.list(request)

def post(self,request):
    return self.create(request)

def put(self,request,id=None):
    return self.update(request,id)

def delete(self,request,id):

models.py

from django.db import models

Create your models here.

class Driver(models.Model):
name=models.CharField(max_length=100)
email=models.EmailField(max_length=100)
phone_number=models.IntegerField(max_length=None)
car_model=models.CharField(max_length=100)
car_year=models.IntegerField(max_length=None)

def  __str__(self):

return self.name

serializer.py

from rest_framework import serializers
from .models import Driver

class DriverSerializer(serializers.ModelSerializer):
class Meta:
model=Driver
fields=['id','name','email','phone_number','car_model','car_year']