Sending a snap to the wrong person ⚠️

Hello,

I sent a snap to someone with a picture of my bedroom curtains, I added the time and a heart, but I sent it to the wrong person (a family friend). I don't know how to delete it, I can't figure it out... If I block the person, will they still be able to see the photo I sent them? Thank you for your response, I would like to resolve this issue before they see it ???????? Thank you for your attention

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