DRF web interface doesn't work as Postman

I’am creating a blog app where only authenticate users can add blogs. I’m using JWT token and on Postman it work’s well and I can add blog’s after I logged in. I want to do it on DRF web interface also but it always tell me that I’m not logged in – I think.

Exception Value:    
Cannot assign "<django.contrib.auth.models.AnonymousUser object at 0x0000021035CA1C50>": "Blog.author" must be a "User" instance.

My views.py

    class BlogList(generics.ListCreateAPIView):
        queryset = Blog.objects.all()
        serializer_class = BlogSerializer
        authentication_classes = [JWTAuthentication]
        #permission_classes = [IsAuthenticated]
        permission_classes = [IsOwnerOrReadOnly]
    
        filter_backends = [SearchFilter]
        search_fields = ["title", "content", "author__username", "author__first_name", "author__last_name"]
    
        def perform_create(self, serializer):
            serializer.save(author=self.request.user)

Serializer.py

class BlogSerializer(serializers.ModelSerializer):
    author = serializers.ReadOnlyField(source="author.username")
    author_first_name = serializers.ReadOnlyField(source="author.first_name")
    author_last_name = serializers.ReadOnlyField(source="author.last_name")
    slug = serializers.ReadOnlyField()
    comments = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
    read_only_fields = ["author", "first_name", "last_name"]

    class Meta:
        model = Blog
        fields = ["id", "title", "content", "status", "author", "comments",  "image",
                  "created_on", "updated_on", "author_first_name", "author_last_name", "slug"]


    def to_representation(self, instance):
        data = super().to_representation(instance)
        user = self.context["request"].user
        if not user.is_authenticated:
            data.pop("slug")
        return data


    def save_author(self, **kwargs):
        if "author" not in self.validated_data:
            self.validated_data["author"] = self.context["request"].user
            return super().save(**kwargs)

    def save(self,**kwargs):
        self.validated_data["slug"] = slugify(self.validated_data.get("title"))
        return super().save(**kwargs)

I don’t know what else I should post here. I tried somehow to DRF web interface add some button like "Authenticate" where you can post your acces token but I can not solve it.