(SOLVED) Server script refuses to FireClient()?

Basically I have a local script that fires a remote event and the server script gets the player's mouse target. I try to then use the mouse target to fire the specific client. Even when I verify that the player exists in game.Players the script says it is Unable to cast a value to Object.

I've simplified the code to only show the FireClient() part of the script.

script.Parent:WaitForChild("ArrestPlayer").OnServerEvent:Connect(function(player, mouse_target)
	if game:GetService("Players"):FindFirstChild(mouse_target) then
		print("yes")
		game:GetService("ReplicatedStorage").GameEvents.Tools.ArrestCoreUI:FireClient(mouse_target)
	else
		print("no")
	end
end)

and in the local script I use .Name so I have no idea why it wouldn't work?

local mouse_target = mouse.Target.Parent.Name
script.Parent:WaitForChild("ArrestPlayer"):FireServer(mouse_target)

Any help would be appreceiated

###This is because you're trying to fire a remote event to a string. The first argument to FireClient is a player to fire to.

script.Parent:WaitForChild("ArrestPlayer").OnServerEvent:Connect(function(player, mouse_target)
    if game:GetService("Players"):FindFirstChild(mouse_target) then
        print("yes")
        game:GetService("ReplicatedStorage").GameEvents.Tools.ArrestCoreUI:FireClient(
            player,
            mouse_target
        ) 

    else

        print("no")
    end
end)

you need to specify the player in the :FireClient()