This happened to me back in the year 2022 when I met my lolo's (grandfather's) doppelganger.
It was a very cold night and the time was 2:30 AM in the morning. Let me explain so you can understand it clearly. My grandfather was in an inuman which is like a drinking event here in the Philippines where you get drunk and have some fun. When my grandfather goes in those certain types of events he goes home very late like I'm talking 5 am or even 7 in the morning.
It was 12:30 am when I was minding my own business scrolling on my phone finding ways to entertain myself because I wasn't sleepy that night. All the lights are out except the outside of my grannie's house where I usually sleep. Grandma's asleep, my brother's asleep which he sleeps right next to me.
Suddenly I heard a knock on our door, my grandma is very responsive and wakes up very fast when she hears a door knock, so she gets up quickly because he was expecting my grandfather. I got up and came to grandma since she doesn't really know if grandpa was really there so I came prepared with a baseball bat. When she opened the door we saw our grand father looking kind of different since he always smiles when he's drunk but he's giving us a frown. I asked grandpa if he enjoyed the inuman but he didn't seem to answer and went to his room with the lights off... I got skeptical since he doesn't sleep with the lights off since he hates the dark. But then at 2 am I heard a knocked at the door again then I saw my real lolo. So I questioned and said that he was in his room sleeping then he said that he was at the inuman all night. So when I opened his room the doppelganger had disappeared.
This my first time sharing this horrifying story ty!