Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
22.7 unless specified otherwise , any notices or other communications to members permitted or required under this agreement , will be in writing and given by airbnb via email , airbnb platform notification , or messaging service ( including sms and wechat ) . 

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