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

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