Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
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if a dispute is not resolved within 15 days after submission , you or fitbit may bring a formal proceeding . 

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. OPTIONS: ["Contract by using", "Arbitration", "Content removal", "Choice of law", "None", "Unilateral termination", "Limitation of liability", "Jurisdiction", "Unilateral change"].