Posted this in ROBLOX's SH forum, they all were like "Must be in a localscript" "Needs to be a localscript" "Localscript" "local", It IS in a LocalScript, they were driving me crazy.
The problem is a chat update function I made based off of a chat gui tutorial on wiki, it's fired everytime a player sends a message or there's a server message (still localscript)
local function Chat(Parent)
for _,v in ipairs(Parent:GetChildren()) do if v.Name:sub(1,8)=="ChatLine" then
local LineNumber=v.Name:sub(9)
if LineNumber=="24" then v:Destroy() else
v.Name="ChatLine"..tostring(tonumber(LineNumber)+1) v:TweenPosition(UDim2.new(0,0,1,v.Position.Y.Offset-14),"Out","Quad",.386,true)
end end end end
This would make call on all messages :Tweenpositon() Up 14. Yes, it works, but if you ever try to spam or chat at the same time another player chats then the message overlaps on another message. Override set to false or true don't help... Here's a pic of the result, I just hope SH lets me put it here.

2 comments
Interesting, never thought of this, like, based on the LineNumber like TweenPosition(UDim2.new(0,0,1,math.abs(14*LineNumber)),"Out","Quad",true)?
Exactly.