How does this man know when I'm online?

whenever I go to instagram, there is a user that I met (he is a stranger) who arrives and connects, it doesn't matter if it's at 1 am or 12 pm but he always comes in when I go in and when I'm not connected he leaves and barely I connect to instagram and that's how it always is.
and I don't know how to know when I'm connected.

The guy is a stranger I met on pornhub but it's starting to seem kind of scary to me and I don't see a way for him to know when I'm online because I never post.
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+1 y
I don't think so because the other night I told him that I was going to sleep and he said that he was also tired so then I got up and it was 1 in the morning and as soon as he came in after 8 minutes and it always happens since I met him
Updates
+1 y
active status is off but he somehow knows when i'm online and when i'm not
How does this man know when I'm online?
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