How would i make it so people get +25% of what they are receiving?

Here's my code:

Also, the FireServer is underlined, why is that?

local remote = game:GetService("ReplicatedStorage"):WaitForChild("BankRobberySuccess")
local id = 4905027

script.Parent.Touched:Connect(function(hit)
	if hit.Parent:FindFirstChild("Humanoid") then
		local player = game.Players:GetPlayerFromCharacter(hit.Parent)
		if player.Robbing.Value == true then
			game.ReplicatedStorage.HideRobberyGUI:FireClient(player)
			player.leaderstats.Money.Value = player.leaderstats.Money.Value + player.CashCollected.Value
			player.CashCollected.Value = 0
			player.Robbing.Value = false
			if game:GetService("MarketplaceService"):UserOwnsGamePassAsync(player.UserId, id) then
				player.CashCollected.Value = player.CashCollected.Value + 20%
			remote:FireServer("B4NK")
			end
		end
	end
end)