Bought a new TT last year. Has a powered awning attached normally at the top inside a tube/sleeve. When it rains it leaks water down the outside of the trailer wall, dripping on anything we have next ...
Take a close look and see if the awning rail is spliced together where it leaks. Mine was and I needed to silicone it to make it stop. Mine even leaked from the run off of condensation from the roof air.