its very easy to hide you Instagram story from selected persons.
open your Instagram profile and click on top right option like this
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now select option "Story Settings" like this
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right now you didnt select any person.
click on top option to select any person like this
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now select any person you want to hide your Instagram story like i select 3 persons like this
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now you select 3 persons from whom you want to hide your Instagram story.
you can check it like this
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thankyou...