Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: @redBus_in #unhappy with #redbus CC, when I talked with them before a week still they didn't initiate the refund of the transaction.
This tweet contains emotions: 
anger, sadness