How to do cipe up with this?

How do u greet someone when they r not close to u but come face to face while buying something or even walking outside because they live in ur apartment building or are from ur friend's family. But they don't reply back and ignore u?
How to do cipe up with this?
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+1 y
It is not cipe... It is cope*
How to do cipe up with this?
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