One of the up front issues is you doing :FireServer(plr) when since its being called from a specific client the server is able to identify what client fired it automatically so you should replace :FireServer(plr) with :FireServer() and the OnServerEvent:Connect(function() to OnServerEvent:Connect(function(plr)
try making sure that the clicked event is actually firing before you go and mess with other things. and the “plr” argument needs to be put on the “OnServerEvent” event, rather than “FireServer”
I don’t really get what you mean, by that, does that mean “FireServer(plr)” is suppose to be FireServer() and “…Connect(function(plr)” into “…Connect:(function(plr)”?
No, when you FireServer from the client, the 1st argument is automatically the player. However, when you’re calling this event on the SERVER, you have to put Player as the 1st arguement.
All you have to fix, is on the server/part script :
game.ReplicatedStorage.Tween.OnServerEvent:Connect(function(player) <— this argument always has to be the player, when you use FireServer
Also, as @Emskipo mentioned, you should avoid naming stuff in the same name, because sometimes it can cause some errors. [In this case, everything seems to be working perfectly.]