Debug body wont show up any message because script didn't had any 'bug'.
Yea thats what i gave you at very first reply on mine here, but then again you mis-explained it or i misunderstood it, anyways, here is what you want:
local marker = createMarker(1514.20679,-1657.22742,12.5,"cylinder",1.2,255,255,255)
function MarkerHit(plr)
if getElementType(plr) == "player" then
if (isPedInVehicle(plr)) then return end
local x, y, z = getElementPosition(plr)
local veh = createVehicle(509, x, y, z)
warpPedIntoVehicle(plr, veh)
end
end
addEventHandler("onMarkerHit", marker, MarkerHit)
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This wont spawn vehicle if you are already in a vehicle.
Thanks a lot I have tried it, now it works