Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
if you purchase a subscription through the google play store , the sale is final and we will not provide a refund . 

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