Flutter stream query not updating value

Stream not updating value. I am using the below stream to get the value and update when user value is null. Everytime it's returning 0. eventhough it has value. please help.

I can't use setstate() since it's a repository of queries.

int? ispublisher = 0;

userRepository.getUser(userKey: userKey!).forEach((users) {
  print(users);
  if (users != null) {
       isPublisher = users.publisher;
   },
});
print(publisher);