Problem with buoyancy for large mass

Hello, I’m trying to simulate a ship floating on water. The ship mass is 1400 Tons (14e5 Kg). When I try to add buoyancy with only one pontoon, nothing happens no matter how much I change the pontoon radius, Buoyancy Coefficient or Max Buoyant Force. Same goes for two pontoons. But, when I add a third pontoon, the ship suddenly starts to act weird when touching the water (either sinking to the bottom or shooting up to the sky) I tried to position multiple pontoons to maintain stability both with relative locations centered on COM and with sockets and it changed nothing. Can someone please help me understand what’s wrong?