Roblox Chat GUI is reaming on screen, despite having code that should remove it?

Hello.

I want to remove the roblox chat GUI, and use a custom chat module.

game:GetService("StarterGui"):SetCoreGuiEnabled(Enum.CoreGuiType.Chat, false)

^^^ This code is what I currently am using, yet it does not function as I intend to. It is located in StarterPlayerScripts.

https://gyazo.com/dc87ce6adb0f5f2535817650a76d5a7e ^^^ This is the studio test view. The chat box remains up, but you cannot type into it. The CUSTOM GUI does not function in studio test view.

https://gyazo.com/bd606713fcf3355d1843c61bb4d0dad8 ^^^ This is the published version. This one has the same chat box, with the new GUI loaded behind it.

Thank you for your work and help in advance!