Error Code 89 Twitter token expired


My twitter app has many users but only for particular users are getting the Token Expired error when they unfollow from my application. I am aware of Rate Limits/Twitter Rules and the app is designed accordingly. I read that if the user will follow/unfollow people in bulk on same day Twitter will stop accepting the request(Aggressive churn) but my user is unfollowing people through my app 3-4 times a week and he is getting token expiry error after unfollowing about 180 people.

Any Ides? What exactly causing token expiry error? Any guidelines so that user won’t get token expiry error immediately.

If my user is caught is aggresive churn behaviour then any guidelines to overcome it.