Error when trying to Save Variables

[Sharp]

Hey all,

I am getting an error when trying to call a function in the OnMoveStop event trying to save variables.

Error: 4857935691701591531:3: attempt to index a nil value
stack traceback:
	4857935691701591531:3: in function '(main chunk)'|r

<GuiXml>
    <Controls>
        <TopLevelControl name="AddonUI" movable="true" mouseEnabled="true" clampedToScreen="true">
            <Dimensions x="180" y="35" />
            <Anchor point="TOPLEFT" offsetX="0" offsetY="0" /> 
			<OnMoveStop>
				Addon.SaveVars( self )
			</OnMoveStop>
            <OnUpdate>
               Update()
            </OnUpdate>			
			<OnMouseEnter>
				DisplayItems()
			</OnMouseEnter>
			<OnMouseExit>
				hideItems()
			</OnMouseExit>
            <Controls>
                <Backdrop name="$(parent)BG" inherits="ZO_ThinBackdrop" />
                <Label name="$(parent)_Label" font="ZoFontGame" color="FFFFFF" wrapMode="ELLIPSIS" horizontalAlignment="CENTER" verticalAlignment="CENTER" text="TEST">
                    <AnchorFill />
                </Label>
            </Controls>
        </TopLevelControl>
    </Controls>
</GuiXml>

function init( eventCode, addOnName )
 
    if ( addOnName ~= Addon.name ) then 
        return 
    end
    
    Addon.defaults = {
        offsetx=30,     
        offsety=1000
    }
    
    Addon.SV = ZO_SavedVars:New( "Addon_SV" , math.floor( Addon.version * 100 ) , nil , Addon.defaults, nil )
 
AddonUI:SetAnchor( TOPLEFT, GuiRoot, TOPLEFT, Addon.SV.offsetx , Addon.SV.offsety )
    
end
 
EVENT_MANAGER:RegisterForEvent( "Addon" , EVENT_ADD_ON_LOADED , init )
 
function Addon.SaveVars( self )
    Addon.SV.offsetx = self:GetLeft()
    Addon.SV.offsety = self:GetTop()
end