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In what way? And what's the solution?
The first coat simply disappears when you apply it. Then each successive coat builds up.That's just how it is, gotta build it (back) up if it hasn't been done a long time / if it has seen a lot of weather, 4+ coats seem a bit much though.
Without seeing it it's hard to judge yet in general I'd probably sandpaper the surface and prime it before coating again.
you're doing it wrong