Task: Determine the prevailing emotional tone of the tweet, categorizing it as either 'neutral or no emotion' or as one or more of the given emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that most accurately represent the tweeter's mental state.
Tweet: Even after @O2 ref the £5k fraud, they still treat me like dirt. No returned calls or apology #shocking #customerservice @mse @resolvercouk
This tweet contains emotions: 
anger, disgust, fear