After resizing player to be bigger, it can't swim in terrain water

I’m in my last stage of my new game creation. I cannot make the game public if I cannot fix this problem. The player cannot swim in water after I scale the player to be bigger.

I’m using terrain grass and the flowers need to be taller than the grass blades and the bush flowers taller than the single flowers. The normal player looks too tiny next to the flowers and the terrain grass blade is a bit tall next to the player. I up the values of BodyDepthScale, BodyHeightScale, BodyWidthScale, and HeadScale to 5.

Player will just float on top of water and won’t be able to go down or any other direction. Changing the WalkSpeed doesn’t help. I checked the Humanoid.Swimming speed and the speed ranges from 0 to 4 even when it’s WalkSpeed is 500 or 1000.

I exhausted google search. There’s no working solution. On this site, someone was having a similar problem and they were told to massless all parts inside character model and then change HumanoidRootPart’s custom density, but that didn’t work for me.

If I change only the height, player will swim normally in water, but player looks too funny like a skinny stick figure. I can script a swimmable part, but player’s swim animation doesn’t look normal and be kicking and flapping arms all over too fast or be standing and floating inside the water part sideways. If I make PrimaryPart’s velocity to zero and use UserInputService to move player, player can look like it’s swimming, but it will not float back up when not swimming. So I don’t want to make a swimmable part if I can use terrain water. I tried changing the Gravity when player’s in water, but it either makes player float or sink, not swim sideways.

Has anyone had this problem before and how did you solve it? Anyone have any idea on what I should try?

How deep is the terrain water?
Maybe thats the case, make the water deeper.

Someone was told to make water deeper while I was searching for a solution, but it didn’t work. I tested on a new empty baseplate with water size of 1024, 512, 1025 and it didn’t work.