Gigi Hadid -- Creepy Fan Scared Me So Bad ... I'm Bolting From My Soho Pad

Gigi Hadid is bailing on her beautiful $2.45 mil NY apartment after an obsessed man allegedly managed to get into the place.

Marcell Porter was arrested on June 29 for making numerous attempts to get into the model’s Soho pad … and cops say one time he was successful getting past security and up into her place.

According to police documents ... Marcell posted creepy messages about Gigi on his Facebook like:

- "I LOVE U. I KNOW EVERYTHING NOW. WAIT FOR ME SOULMATE."
- "WHY CAN'T YOU CALL ME? I WILL TALK TO U IN PERSON ASAP. I LOVE YOU ONCE AGAIN"

Porter was charged with one count of 4th degree stalking -- but the damage is done for Gigi. She's already listed the apartment.