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?

Any ideas please?