Block user
If you are using the web:
After login, you can go to the user's profile page and click the options button below the text box
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Click "Block"
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Then click "Block user" to block the user
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If you are using iOS app:
After login, you can go to the user's profile page and click the button on the top right
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Click "Block user"
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Then click "Yes" to block the user
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