Pull user details with ID error



I have multiple different Screen Names which i am pulling ID’s of their flowers, and for all of the ID’s pulled, i am trying to find the location for the followers which is working fine. But for certain followers ID’s i am getting error 404, any ideas why this could be the case. For all screen name the total number of ID’s returned is equal to the page followers, it when i am using the lookup method to search for the user information I am getting error 404,


These users might not exist any more – the returns from followers/ids and friends/ids can sometimes return IDs that no longer exist.