Im making a function and connecting with parameters is causing this error
You cannot pass values like that, if there is a value to pass, Roblox will automatically pass it, like when a player joins.
I believe it has to do with how you call the Connect with custom parameters, see this solution here:
buttonHover(), you pass the value which is returned by this function.
However, you need to pass a function itself to the first parameter of Connect. That’s why you either do:
signal:Connect(buttonHover) -- or with custom parameters: signal:Connect(function() buttonHover('some', 'parameters') end)